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        <link:definition>1050 - Disclosure - Other Liabilities (Tables)</link:definition>
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        <link:definition>1051 - Disclosure - Equity (Tables)</link:definition>
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        <link:definition>1052 - Disclosure - Share-based Compensation (Tables)</link:definition>
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        <link:definition>1053 - Disclosure - Employee Benefit Expenses (Tables)</link:definition>
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        <link:definition>1054 - Disclosure - Income taxes (Tables)</link:definition>
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        <link:definition>1055 - Disclosure - Commitments and contingencies (Tables)</link:definition>
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        <link:definition>1056 - Disclosure - Related Party Transactions (Tables)</link:definition>
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        <link:definition>1057 - Disclosure - Segment Information (Tables)</link:definition>
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        <link:definition>1058 - Disclosure - Earnings per Share (Tables)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:definition>1059 - Disclosure - Organization and nature of business - Additional Information (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:definition>1060 - Disclosure - Basis of presentation and description of the transactions - Additional Information (Details)</link:definition>
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      <link:roleType roleURI="http://www.hmhw.com/role/BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesDetails" id="BasisOfPresentationAndSummaryOfSignificantAccountingPoliciesDetails">
        <link:definition>1061 - Disclosure - Basis of Presentation and Summary of Significant Accounting Policies (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:definition>1062 - Disclosure - Basis of Presentation and Summary of Significant Accounting Policies - Schedule of Property Plant And Equipment Useful Life (Details)</link:definition>
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        <link:definition>1063 - Disclosure - Notes to unaudited pro forma consolidated balance sheet - Additional Information (Details)</link:definition>
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        <link:definition>1064 - Disclosure - Notes to Unaudited Pro Forma Consolidated Statement of Income - Additional Information (Details)</link:definition>
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        <link:definition>1065 - Disclosure - Notes to Unaudited Pro Forma Consolidated Statement of Income - Schedule of Earnings Per Share, Basic and Diluted (Details)</link:definition>
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      </link:roleType>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      </link:roleType>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1080 - Disclosure - Financial Instruments - Schedule Of Fair Value Of The Derivative Financial Instruments And A Maturity Analysis Of The Derivatives Cash Flows (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
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      </link:roleType>
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        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/LeasesScheduleOfLesseeOperatingLeaseLiabilityToBePaidMaturityDetails" id="LeasesScheduleOfLesseeOperatingLeaseLiabilityToBePaidMaturityDetails">
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        <link:usedOn>link:definitionLink</link:usedOn>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/DebtShortTermAndLongTermDebtDetails" id="DebtShortTermAndLongTermDebtDetails">
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1092 - Disclosure - Debt - Schedule of Maturities of Long-Term Debt (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/RevenueFromContractsWithCustomersDisaggregatedRevenueDetails" id="RevenueFromContractsWithCustomersDisaggregatedRevenueDetails">
        <link:definition>1094 - Disclosure - Revenue from Contracts with Customers - Disaggregated Revenue (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/RevenueFromContractsWithCustomersContractAssetsDetails" id="RevenueFromContractsWithCustomersContractAssetsDetails">
        <link:definition>1095 - Disclosure - Revenue from Contracts with Customers - Contract Assets (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/RevenueFromContractsWithCustomersContractLiabilitiesDetails" id="RevenueFromContractsWithCustomersContractLiabilitiesDetails">
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.hmhw.com/role/AccruedExpensesDetails" id="AccruedExpensesDetails">
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.hmhw.com/role/AccruedExpensesWarrantyLiabilityDetails" id="AccruedExpensesWarrantyLiabilityDetails">
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.hmhw.com/role/AccruedExpensesAdditionalInformationDetails" id="AccruedExpensesAdditionalInformationDetails">
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/OtherLiabilitiesSummaryOfOtherNoncurrentLiabilitiesDetails" id="OtherLiabilitiesSummaryOfOtherNoncurrentLiabilitiesDetails">
        <link:definition>1100 - Disclosure - Other Liabilities- Summary Of Other Noncurrent Liabilities (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.hmhw.com/role/OtherLiabilitiesSummaryOfOtherNoncurrentLiabilitiesParentheticalDetails" id="OtherLiabilitiesSummaryOfOtherNoncurrentLiabilitiesParentheticalDetails">
        <link:definition>1101 - Disclosure - Other liabilities - Summary Of Other Noncurrent Liabilities (Parenthetical) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.hmhw.com/role/EquityAdditionalInformationDetails" id="EquityAdditionalInformationDetails">
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/EquityChangeInOwnershipOfHmhBVDetails" id="EquityChangeInOwnershipOfHmhBVDetails">
        <link:definition>1103 - Disclosure - Equity - Change in Ownership of HMH B.V (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/ShareBasedCompensationAdditionalInformationDetailsAlternate" id="ShareBasedCompensationAdditionalInformationDetailsAlternate">
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/ShareBasedCompensationRsusAndPsusActivityDetails" id="ShareBasedCompensationRsusAndPsusActivityDetails">
        <link:definition>1107 - Disclosure - Share-based Compensation - RSUs and PSUs Activity (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/ShareBasedCompensationWeightedAverageAssumptionsDetails" id="ShareBasedCompensationWeightedAverageAssumptionsDetails">
        <link:definition>1108 - Disclosure - Share-based Compensation - Weighted Average Assumptions (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/EmployeeBenefitExpensesScheduleOfTheAccumulatedBenefitObligationDetails" id="EmployeeBenefitExpensesScheduleOfTheAccumulatedBenefitObligationDetails">
        <link:definition>1110 - Disclosure - Employee Benefit Expenses - Schedule of the accumulated benefit obligation (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1111 - Disclosure - Employee Benefit Expenses - Schedule of The Amounts Recognized in The Consolidated Balance Sheets (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1112 - Disclosure - Employee Benefit Expenses - Schedule of The Plans With Projected Benefit Obligations and Accumulated Benefit (Details)</link:definition>
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        <link:definition>1113 - Disclosure - Employee Benefit Expenses - Schedule of Net Periodic Cost Recognized in Selling, General and Administrative Expenses (Details)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1114 - Disclosure - Employee Benefit Expenses - Schedule of The Weighted Average Assumptions Used To Determine Net Periodic (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1115 - Disclosure - Employee Benefit Expenses - Schedule of Amount Recorded Before-Tax in Accumulated Other Comprehensive Income (Loss) (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1116 - Disclosure - Employee Benefit Expenses - Schedule of The Current Life Expectancy After Retirement (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1117 - Disclosure - Employee Benefit Expenses - Schedule of The Pension Plans In Norway (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1118 - Disclosure - Employee Benefit Expenses - Schedule of The Expected Benefit Payments For Pension Benefits (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1119 - Disclosure - Employee Benefit Expenses - Schedule of The Pension Plans In Norway (parenthetical) (Details)</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.hmhw.com/role/EmployeeBenefitExpensesAdditionalInformationDetails" id="EmployeeBenefitExpensesAdditionalInformationDetails">
        <link:definition>1120 - Disclosure - Employee Benefit Expenses - Additional information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.hmhw.com/role/IncomeTaxesAdditionalInformationDetails" id="IncomeTaxesAdditionalInformationDetails">
        <link:definition>1121 - Disclosure - Income Taxes- Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/IncomeTaxesScheduleOfComponentsOfIncomeTaxExpenseDetails" id="IncomeTaxesScheduleOfComponentsOfIncomeTaxExpenseDetails">
        <link:definition>1122 - Disclosure - Income taxes - Schedule of Components of Income Tax Expense (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1123 - Disclosure - Income taxes - Schedule of Income before Income Tax, Domestic and Foreign (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/IncomeTaxesScheduleOfEffectiveIncomeTaxRateReconciliationDetails" id="IncomeTaxesScheduleOfEffectiveIncomeTaxRateReconciliationDetails">
        <link:definition>1124 - Disclosure - Income taxes - Schedule of Effective Income Tax Rate Reconciliation (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/IncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetails" id="IncomeTaxesScheduleOfDeferredTaxAssetsAndLiabilitiesDetails">
        <link:definition>1125 - Disclosure - Income taxes -  Schedule of Deferred Tax Assets and Liabilities (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/IncomeTaxesScheduleOfUnrecognizedTaxBenefitsRollForwardDetails" id="IncomeTaxesScheduleOfUnrecognizedTaxBenefitsRollForwardDetails">
        <link:definition>1126 - Disclosure - Income Taxes - Schedule of Unrecognized Tax Benefits Roll Forward (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/IncomeTaxesScheduleOfEffectiveIncomeTaxRateReconciliationParentheticalDetails" id="IncomeTaxesScheduleOfEffectiveIncomeTaxRateReconciliationParentheticalDetails">
        <link:definition>1127 - Disclosure - Income taxes - Schedule of Effective Income Tax Rate Reconciliation (Parenthetical) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.hmhw.com/role/CommitmentsAndContingenciesAdditionalInformationDetails" id="CommitmentsAndContingenciesAdditionalInformationDetails">
        <link:definition>1128 - Disclosure - Commitments and Contingencies - Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1129 - Disclosure - Commitments and Contingencies - Changes in Provision Balance for Restructuring and Other Charges (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.hmhw.com/role/RelatedPartyTransactionsScheduleOfRelatedPartyTransactionsDetails" id="RelatedPartyTransactionsScheduleOfRelatedPartyTransactionsDetails">
        <link:definition>1130 - Disclosure - Related Party Transactions - Schedule of Related Party Transactions (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.hmhw.com/role/RelatedPartyTransactionsAdditionalInformationDetails" id="RelatedPartyTransactionsAdditionalInformationDetails">
        <link:definition>1131 - Disclosure - Related Party Transactions - Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.hmhw.com/role/SegmentInformationAdditionalInformationDetails" id="SegmentInformationAdditionalInformationDetails">
        <link:definition>1132 - Disclosure - Segment Information - Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/SegmentInformationReconciliationOfReportableSegmentRevenuesDetails" id="SegmentInformationReconciliationOfReportableSegmentRevenuesDetails">
        <link:definition>1133 - Disclosure - Segment Information - Reconciliation of Reportable Segment Revenues (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.hmhw.com/role/SegmentInformationReconciliationOfSegmentPerformanceDetails" id="SegmentInformationReconciliationOfSegmentPerformanceDetails">
        <link:definition>1134 - Disclosure - Segment Information - Reconciliation of Segment Performance (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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      <link:roleType roleURI="http://www.hmhw.com/role/SegmentInformationScheduleOfRevenueAndLongLivedAssetsOnTheBasisOfGeographyDetails" id="SegmentInformationScheduleOfRevenueAndLongLivedAssetsOnTheBasisOfGeographyDetails">
        <link:definition>1135 - Disclosure - Segment Information - Schedule of revenue and long-lived assets on the basis of geography (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.hmhw.com/role/SegmentInformationParentheticalDetails" id="SegmentInformationParentheticalDetails">
        <link:definition>1136 - Disclosure - Segment Information (Parenthetical) (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://www.hmhw.com/role/EarningsPerShareAdditionalInformationDetails" id="EarningsPerShareAdditionalInformationDetails">
        <link:definition>1137 - Disclosure - Earnings per Share - Additional Information (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1138 - Disclosure - Earnings per Share - Basic and Diluted Net Income (Loss) Per Share (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1139 - Disclosure - Earnings per Share - Potential Common Shares Excluded from Diluted Share Calculation (Details)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
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        <link:definition>1140 - Statement - Leases - Schedule of Lessee, Operating Lease, Liability, to be Paid, Maturity (Details) Alternate 1</link:definition>
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        <link:usedOn>link:definitionLink</link:usedOn>
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          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentInformationLineItems" xlink:to="lab_dei_DocumentInformationLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_DocumentType" xlink:label="loc_dei_DocumentType" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_DocumentType" xml:lang="en-US">Document Type</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_DocumentType" xml:lang="en-US">Document Type</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_DocumentType" xlink:to="lab_dei_DocumentType" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityRegistrantName" xlink:label="loc_dei_EntityRegistrantName" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntityRegistrantName" xml:lang="en-US">Entity Registrant Name</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_EntityRegistrantName" xml:lang="en-US">Entity Registrant Name</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityRegistrantName" xlink:to="lab_dei_EntityRegistrantName" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityIncorporationStateCountryCode" xlink:label="loc_dei_EntityIncorporationStateCountryCode" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntityIncorporationStateCountryCode" xml:lang="en-US">Entity Incorporation, State or Country Code</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_EntityIncorporationStateCountryCode" xml:lang="en-US">Entity Incorporation, State or Country Code</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityIncorporationStateCountryCode" xlink:to="lab_dei_EntityIncorporationStateCountryCode" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityTaxIdentificationNumber" xlink:label="loc_dei_EntityTaxIdentificationNumber" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntityTaxIdentificationNumber" xml:lang="en-US">Entity Tax Identification Number</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_EntityTaxIdentificationNumber" xml:lang="en-US">Entity Tax Identification Number</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityTaxIdentificationNumber" xlink:to="lab_dei_EntityTaxIdentificationNumber" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressAddressLine1" xlink:label="loc_dei_EntityAddressAddressLine1" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntityAddressAddressLine1" xml:lang="en-US">Entity Address, Address Line One</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_EntityAddressAddressLine1" xml:lang="en-US">Entity Address, Address Line One</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityAddressAddressLine1" xlink:to="lab_dei_EntityAddressAddressLine1" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressCityOrTown" xlink:label="loc_dei_EntityAddressCityOrTown" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntityAddressCityOrTown" xml:lang="en-US">Entity Address, City or Town</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_EntityAddressCityOrTown" xml:lang="en-US">Entity Address, City or Town</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityAddressCityOrTown" xlink:to="lab_dei_EntityAddressCityOrTown" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressStateOrProvince" xlink:label="loc_dei_EntityAddressStateOrProvince" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntityAddressStateOrProvince" xml:lang="en-US">Entity Address, State or Province</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_EntityAddressStateOrProvince" xml:lang="en-US">Entity Address, State or Province</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityAddressStateOrProvince" xlink:to="lab_dei_EntityAddressStateOrProvince" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressPostalZipCode" xlink:label="loc_dei_EntityAddressPostalZipCode" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntityAddressPostalZipCode" xml:lang="en-US">Entity Address, Postal Zip Code</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_EntityAddressPostalZipCode" xml:lang="en-US">Entity Address, Postal Zip Code</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityAddressPostalZipCode" xlink:to="lab_dei_EntityAddressPostalZipCode" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_CityAreaCode" xlink:label="loc_dei_CityAreaCode" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_CityAreaCode" xml:lang="en-US">City Area Code</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_CityAreaCode" xml:lang="en-US">City Area Code</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_CityAreaCode" xlink:to="lab_dei_CityAreaCode" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_LocalPhoneNumber" xlink:label="loc_dei_LocalPhoneNumber" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_LocalPhoneNumber" xml:lang="en-US">Local Phone Number</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_LocalPhoneNumber" xml:lang="en-US">Local Phone Number</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_LocalPhoneNumber" xlink:to="lab_dei_LocalPhoneNumber" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntitySmallBusiness" xlink:label="loc_dei_EntitySmallBusiness" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntitySmallBusiness" xml:lang="en-US">Entity Small Business</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_EntitySmallBusiness" xml:lang="en-US">Entity Small Business</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntitySmallBusiness" xlink:to="lab_dei_EntitySmallBusiness" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityFilerCategory" xlink:label="loc_dei_EntityFilerCategory" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntityFilerCategory" xml:lang="en-US">Entity Filer Category</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_EntityFilerCategory" xml:lang="en-US">Entity Filer Category</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityFilerCategory" xlink:to="lab_dei_EntityFilerCategory" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityEmergingGrowthCompany" xlink:label="loc_dei_EntityEmergingGrowthCompany" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntityEmergingGrowthCompany" xml:lang="en-US">Entity Emerging Growth Company</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_EntityEmergingGrowthCompany" xml:lang="en-US">Entity Emerging Growth Company</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityEmergingGrowthCompany" xlink:to="lab_dei_EntityEmergingGrowthCompany" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityExTransitionPeriod" xlink:label="loc_dei_EntityExTransitionPeriod" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntityExTransitionPeriod" xml:lang="en-US">Entity Ex Transition Period</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_EntityExTransitionPeriod" xml:lang="en-US">Entity Ex Transition Period</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityExTransitionPeriod" xlink:to="lab_dei_EntityExTransitionPeriod" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityCentralIndexKey" xlink:label="loc_dei_EntityCentralIndexKey" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntityCentralIndexKey" xml:lang="en-US">Entity Central Index Key</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_EntityCentralIndexKey" xml:lang="en-US">Entity Central Index Key</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityCentralIndexKey" xlink:to="lab_dei_EntityCentralIndexKey" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_AmendmentFlag" xlink:label="loc_dei_AmendmentFlag" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_AmendmentFlag" xml:lang="en-US">Amendment Flag</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_dei_AmendmentFlag" xml:lang="en-US">Amendment Flag</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_AmendmentFlag" xlink:to="lab_dei_AmendmentFlag" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_ContactPersonnelName" xlink:label="loc_dei_ContactPersonnelName" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_ContactPersonnelName" xml:lang="en-US">Contact Personnel Name</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_ContactPersonnelName" xlink:to="lab_dei_ContactPersonnelName" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityPrimarySicNumber" xlink:label="loc_dei_EntityPrimarySicNumber" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntityPrimarySicNumber" xml:lang="en-US">Entity Primary SIC Number</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityPrimarySicNumber" xlink:to="lab_dei_EntityPrimarySicNumber" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_EntityAddressesAddressTypeAxis" xlink:label="loc_dei_EntityAddressesAddressTypeAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_EntityAddressesAddressTypeAxis" xml:lang="en-US">Entity Addresses, Address Type [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_EntityAddressesAddressTypeAxis" xlink:to="lab_dei_EntityAddressesAddressTypeAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_AddressTypeDomain" xlink:label="loc_dei_AddressTypeDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_AddressTypeDomain" xml:lang="en-US">Address Type [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_AddressTypeDomain" xlink:to="lab_dei_AddressTypeDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2026/dei-2026.xsd#dei_BusinessContactMember" xlink:label="loc_dei_BusinessContactMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_dei_BusinessContactMember" xml:lang="en-US">Business Contact [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_dei_BusinessContactMember" xlink:to="lab_dei_BusinessContactMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeStatementAbstract" xlink:label="loc_us-gaap_IncomeStatementAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeStatementAbstract" xml:lang="en-US">Income Statement [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncomeStatementAbstract" xml:lang="en-US">Condensed Consolidated Statements of Income</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementAbstract" xlink:to="lab_us-gaap_IncomeStatementAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementTable" xlink:label="loc_us-gaap_StatementTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StatementTable" xml:lang="en-US">Statement [Table]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StatementTable" xml:lang="en-US">Statement [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementTable" xlink:to="lab_us-gaap_StatementTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductOrServiceAxis" xlink:label="loc_srt_ProductOrServiceAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_ProductOrServiceAxis" xml:lang="en-US">Product and Service [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_ProductOrServiceAxis" xml:lang="en-US">Product and Service [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ProductOrServiceAxis" xlink:to="lab_srt_ProductOrServiceAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ProductsAndServicesDomain" xlink:label="loc_srt_ProductsAndServicesDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_ProductsAndServicesDomain" xml:lang="en-US">Product and Service [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_ProductsAndServicesDomain" xml:lang="en-US">Product and Service [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ProductsAndServicesDomain" xlink:to="lab_srt_ProductsAndServicesDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ServiceMember" xlink:label="loc_us-gaap_ServiceMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ServiceMember" xml:lang="en-US">Service [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ServiceMember" xml:lang="en-US">Service</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ServiceMember" xml:lang="en-US">Service revenue</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ServiceMember" xlink:to="lab_us-gaap_ServiceMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProductMember" xlink:label="loc_us-gaap_ProductMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProductMember" xml:lang="en-US">Product [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ProductMember" xml:lang="en-US">Product</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductMember" xlink:to="lab_us-gaap_ProductMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_SparePartsMember" xlink:label="loc_hmh_SparePartsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_SparePartsMember" xml:lang="en-US">Spare Parts [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_hmh_SparePartsMember" xml:lang="en-US">Spare Parts</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_SparePartsMember" xml:lang="en-US">Spare parts revenue</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_SparePartsMember" xlink:to="lab_hmh_SparePartsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_SparePartsMember" xml:lang="en-US">Spare Parts</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xml:lang="en-US">Related and Nonrelated Parties [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xml:lang="en-US">Related and Nonrelated Parties [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaap_RelatedPartyDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RelatedPartyDomain" xml:lang="en-US">Related and Nonrelated Parties [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RelatedPartyDomain" xml:lang="en-US">Related and Nonrelated Parties [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyDomain" xlink:to="lab_us-gaap_RelatedPartyDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NonrelatedPartyMember" xlink:label="loc_us-gaap_NonrelatedPartyMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NonrelatedPartyMember" xml:lang="en-US">Nonrelated Party [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NonrelatedPartyMember" xml:lang="en-US">Nonrelated Party</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NonrelatedPartyMember" xlink:to="lab_us-gaap_NonrelatedPartyMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyMember" xlink:label="loc_us-gaap_RelatedPartyMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RelatedPartyMember" xml:lang="en-US">Related Party [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RelatedPartyMember" xml:lang="en-US">Related Party</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyMember" xlink:to="lab_us-gaap_RelatedPartyMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementLineItems" xlink:label="loc_us-gaap_StatementLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StatementLineItems" xml:lang="en-US">Statement [Line Items]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StatementLineItems" xml:lang="en-US">Statement [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementLineItems" xlink:to="lab_us-gaap_StatementLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerAbstract" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerAbstract" xml:lang="en-US">Revenue from Contract with Customer [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerAbstract" xml:lang="en-US">Revenue</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueFromContractWithCustomerAbstract" xlink:to="lab_us-gaap_RevenueFromContractWithCustomerAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax" xml:lang="en-US">Revenue from Contract with Customer, Including Assessed Tax</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax" xml:lang="en-US">Total revenue</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax" xml:lang="en-US">Revenue</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/definitionGuidance" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax" xml:lang="en-US">Revenue from external customers</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax" xlink:to="lab_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingExpensesAbstract" xlink:label="loc_us-gaap_OperatingExpensesAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingExpensesAbstract" xml:lang="en-US">Operating Expenses [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OperatingExpensesAbstract" xml:lang="en-US">Operating expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingExpensesAbstract" xlink:to="lab_us-gaap_OperatingExpensesAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServicesSold" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSold" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CostOfGoodsAndServicesSold" xml:lang="en-US">Cost of Product and Service Sold</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CostOfGoodsAndServicesSold" xml:lang="en-US">Total cost of sales</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_CostOfGoodsAndServicesSold" xml:lang="en-US">Cost of sales</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CostOfGoodsAndServicesSold" xlink:to="lab_us-gaap_CostOfGoodsAndServicesSold" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SellingGeneralAndAdministrativeExpense" xlink:label="loc_us-gaap_SellingGeneralAndAdministrativeExpense" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SellingGeneralAndAdministrativeExpense" xml:lang="en-US">Selling, General and Administrative Expense</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SellingGeneralAndAdministrativeExpense" xml:lang="en-US">Selling, general and administrative expenses</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_SellingGeneralAndAdministrativeExpense" xml:lang="en-US">Selling, general and administrative expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SellingGeneralAndAdministrativeExpense" xlink:to="lab_us-gaap_SellingGeneralAndAdministrativeExpense" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ResearchAndDevelopmentExpense" xlink:label="loc_us-gaap_ResearchAndDevelopmentExpense" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ResearchAndDevelopmentExpense" xml:lang="en-US">Research and Development Expense</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ResearchAndDevelopmentExpense" xml:lang="en-US">Research and development expenses</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_ResearchAndDevelopmentExpense" xml:lang="en-US">Research and development expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ResearchAndDevelopmentExpense" xlink:to="lab_us-gaap_ResearchAndDevelopmentExpense" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringCostsAndAssetImpairmentCharges" xlink:label="loc_us-gaap_RestructuringCostsAndAssetImpairmentCharges" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RestructuringCostsAndAssetImpairmentCharges" xml:lang="en-US">Restructuring Costs and Asset Impairment Charges</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_RestructuringCostsAndAssetImpairmentCharges" xml:lang="en-US">Restructuring and other expenses (income), net</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_RestructuringCostsAndAssetImpairmentCharges" xml:lang="en-US">Restructuring and other expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringCostsAndAssetImpairmentCharges" xlink:to="lab_us-gaap_RestructuringCostsAndAssetImpairmentCharges" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostsAndExpenses" xlink:label="loc_us-gaap_CostsAndExpenses" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CostsAndExpenses" xml:lang="en-US">Costs and Expenses</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_CostsAndExpenses" xml:lang="en-US">Total operating expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CostsAndExpenses" xlink:to="lab_us-gaap_CostsAndExpenses" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingIncomeLoss" xml:lang="en-US">Operating Income (Loss)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_OperatingIncomeLoss" xml:lang="en-US">Operating income (loss)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingIncomeLoss" xlink:to="lab_us-gaap_OperatingIncomeLoss" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCurrencyTransactionGainLossBeforeTax" xlink:label="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax" xml:lang="en-US">Gain (Loss), Foreign Currency Transaction, before Tax</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax" xml:lang="en-US">Foreign currency gain (loss), net</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax" xml:lang="en-US">Foreign currency gain (loss)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax" xlink:to="lab_us-gaap_ForeignCurrencyTransactionGainLossBeforeTax" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNonoperatingIncomeExpense" xlink:label="loc_us-gaap_OtherNonoperatingIncomeExpense" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherNonoperatingIncomeExpense" xml:lang="en-US">Other Nonoperating Income (Expense)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherNonoperatingIncomeExpense" xml:lang="en-US">Other non-operating income (loss)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherNonoperatingIncomeExpense" xlink:to="lab_us-gaap_OtherNonoperatingIncomeExpense" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpenseNonoperating" xlink:label="loc_us-gaap_InterestExpenseNonoperating" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InterestExpenseNonoperating" xml:lang="en-US">Interest Expense, Nonoperating</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_InterestExpenseNonoperating" xml:lang="en-US">Interest income (expense), net</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_InterestExpenseNonoperating" xml:lang="en-US">Interest expense, net</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_InterestExpenseNonoperating" xml:lang="en-US">Interest expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestExpenseNonoperating" xlink:to="lab_us-gaap_InterestExpenseNonoperating" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xml:lang="en-US">Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xml:lang="en-US">Income (loss) before income taxes</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xml:lang="en-US">Income before income taxes</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" xlink:to="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_IncomeTaxExpenseBenefit" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit" xml:lang="en-US">Income Tax Expense (Benefit)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit" xml:lang="en-US">Income tax (expense) benefit</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_IncomeTaxExpenseBenefit" xml:lang="en-US">Income tax expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxExpenseBenefit" xlink:to="lab_us-gaap_IncomeTaxExpenseBenefit" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaap_ProfitLoss" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProfitLoss" xml:lang="en-US">Net Income (Loss), Including Portion Attributable to Noncontrolling Interest</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_ProfitLoss" xml:lang="en-US">Net income (loss)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ProfitLoss" xml:lang="en-US">Net income (loss)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/definitionGuidance" xlink:label="lab_us-gaap_ProfitLoss" xml:lang="en-US">Net income (loss)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ProfitLoss" xml:lang="en-US">Net income</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProfitLoss" xlink:to="lab_us-gaap_ProfitLoss" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLossAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest" xml:lang="en-US">Net Income (Loss) Attributable to Noncontrolling Interest</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest" xml:lang="en-US">Less: Net income (loss) attributable to&#160;non-controlling&#160;interests</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest" xml:lang="en-US">Net income attributable&#160;to&#160;non-controlling&#160;interests</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest" xlink:to="lab_us-gaap_NetIncomeLossAttributableToNoncontrollingInterest" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetIncomeLoss" xml:lang="en-US">Net Income (Loss) Attributable to Parent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_NetIncomeLoss" xml:lang="en-US">Net income (loss) attributable to HMH Holding Inc.</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NetIncomeLoss" xml:lang="en-US">Net income attributable to HMH Holding Inc.</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Basic</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xml:lang="en-US">Weighted-average shares of common stock for HMH and HMH B.V. outstanding&#8212;Basic (in shares)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/definitionGuidance" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xml:lang="en-US">Weighted average shares of Class&#160;A common stock outstanding (basic)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xml:lang="en-US">Weighted-average shares of common stock for HMH and HMH B.V. outstanding&#8212;basic (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:to="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" />
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Diluted</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xml:lang="en-US">Weighted-average shares of common stock for HMH and HMH B.V. outstanding&#8212;Diluted (in shares)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xml:lang="en-US">Weighted average shares of Class&#160;A common stock outstanding (diluted)</link:label>
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          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:to="lab_us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" />
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_ConsolidatedEntitiesAxis" xml:lang="en-US">Consolidated Entities [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_ConsolidatedEntitiesAxis" xml:lang="en-US">Legal Entity [Axis]</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_ConsolidatedEntitiesDomain" xml:lang="en-US">Consolidated Entities [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_ConsolidatedEntitiesDomain" xml:lang="en-US">Entity [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ConsolidatedEntitiesDomain" xlink:to="lab_srt_ConsolidatedEntitiesDomain" />
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          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_HMHHoldingBVAndSubsidiariesMember" xlink:to="lab_hmh_HMHHoldingBVAndSubsidiariesMember" />
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_HMHHoldingIncMember" xml:lang="en-US">HMH Holding Inc. [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_HMHHoldingIncMember" xml:lang="en-US">HMH Holding Inc.</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_HMHHoldingIncMember" xlink:to="lab_hmh_HMHHoldingIncMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_HMHHoldingIncMember" xml:lang="en-US">HMH Holding Inc.</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_StatementScenarioAxis" xml:lang="en-US">Scenario [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_StatementScenarioAxis" xlink:to="lab_srt_StatementScenarioAxis" />
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_ScenarioUnspecifiedDomain" xml:lang="en-US">Scenario [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ScenarioUnspecifiedDomain" xlink:to="lab_srt_ScenarioUnspecifiedDomain" />
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_HistoricalMember" xml:lang="en-US">Historical [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_HistoricalMember" xlink:to="lab_hmh_HistoricalMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_CorporateReorganizationsAdjustmentMember" xlink:label="loc_hmh_CorporateReorganizationsAdjustmentMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_CorporateReorganizationsAdjustmentMember" xml:lang="en-US">Corporate Reorganizations Adjustment [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_CorporateReorganizationsAdjustmentMember" xlink:to="lab_hmh_CorporateReorganizationsAdjustmentMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OfferingTransactionsAdjustmentsMember" xlink:label="loc_hmh_OfferingTransactionsAdjustmentsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OfferingTransactionsAdjustmentsMember" xml:lang="en-US">Offering Transactions Adjustments [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OfferingTransactionsAdjustmentsMember" xlink:to="lab_hmh_OfferingTransactionsAdjustmentsMember" />
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_ProFormaMember" xml:lang="en-US">Pro Forma [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ProFormaMember" xlink:to="lab_srt_ProFormaMember" />
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          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" xlink:to="lab_us-gaap_StatementOfIncomeAndComprehensiveIncomeAbstract" />
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax" xml:lang="en-US">Tax benefit (expense) on effect of changes in benefit plans</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax" xml:lang="en-US">Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax" xml:lang="en-US">Net effect of changes in benefit plans, after taxes</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax" xml:lang="en-US">Other Comprehensive Income (Loss), Net of Tax</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax" xml:lang="en-US">Total other comprehensive income (loss)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax" xml:lang="en-US">Other comprehensive income (loss)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeLossNetOfTax" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest" xml:lang="en-US">Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest" xml:lang="en-US">Comprehensive income (loss)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest" xlink:to="lab_us-gaap_ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest" xml:lang="en-US">Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest" xml:lang="en-US">Less: Comprehensive income (loss) attributable to non-controlling interests</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest" xlink:to="lab_us-gaap_ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComprehensiveIncomeNetOfTax" xlink:label="loc_us-gaap_ComprehensiveIncomeNetOfTax" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTax" xml:lang="en-US">Comprehensive Income (Loss), Net of Tax, Attributable to Parent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_ComprehensiveIncomeNetOfTax" xml:lang="en-US">Comprehensive income (loss) attributable to HMH Holding Inc.</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComprehensiveIncomeNetOfTax" xlink:to="lab_us-gaap_ComprehensiveIncomeNetOfTax" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfFinancialPositionAbstract" xlink:label="loc_us-gaap_StatementOfFinancialPositionAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StatementOfFinancialPositionAbstract" xml:lang="en-US">Statement of Financial Position [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StatementOfFinancialPositionAbstract" xml:lang="en-US">Condensed Consolidated Balance Sheets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfFinancialPositionAbstract" xlink:to="lab_us-gaap_StatementOfFinancialPositionAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassAMember" xlink:label="loc_us-gaap_CommonClassAMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonClassAMember" xml:lang="en-US">Common Class A [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CommonClassAMember" xml:lang="en-US">Class A Common Stock</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_CommonClassAMember" xml:lang="en-US">Class A common stock</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonClassAMember" xlink:to="lab_us-gaap_CommonClassAMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonClassBMember" xlink:label="loc_us-gaap_CommonClassBMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonClassBMember" xml:lang="en-US">Common Class B [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CommonClassBMember" xml:lang="en-US">Class B Common Stock</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_CommonClassBMember" xml:lang="en-US">Class B common stock</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonClassBMember" xlink:to="lab_us-gaap_CommonClassBMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xml:lang="en-US">Intangible Asset, Finite-Lived, Class [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xml:lang="en-US">Intangible Asset, Finite-Lived, Class [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xml:lang="en-US">Intangible Asset, Finite-Lived, Class [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xml:lang="en-US">Intangible Asset, Finite-Lived, Class [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CustomerRelationshipsMember" xlink:label="loc_us-gaap_CustomerRelationshipsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CustomerRelationshipsMember" xml:lang="en-US">Customer Relationships [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CustomerRelationshipsMember" xml:lang="en-US">Customer relationships</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CustomerRelationshipsMember" xlink:to="lab_us-gaap_CustomerRelationshipsMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherIntangibleAssetsMember" xlink:label="loc_us-gaap_OtherIntangibleAssetsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherIntangibleAssetsMember" xml:lang="en-US">Other Intangible Assets [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherIntangibleAssetsMember" xml:lang="en-US">Other intangible assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherIntangibleAssetsMember" xlink:to="lab_us-gaap_OtherIntangibleAssetsMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsAbstract" xlink:label="loc_us-gaap_AssetsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AssetsAbstract" xml:lang="en-US">Assets [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AssetsAbstract" xml:lang="en-US">Assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsAbstract" xlink:to="lab_us-gaap_AssetsAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrentAbstract" xlink:label="loc_us-gaap_AssetsCurrentAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AssetsCurrentAbstract" xml:lang="en-US">Assets, Current [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AssetsCurrentAbstract" xml:lang="en-US">Current assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsCurrentAbstract" xlink:to="lab_us-gaap_AssetsCurrentAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue" xml:lang="en-US">Cash and Cash Equivalent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue" xml:lang="en-US">Cash and cash equivalents</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:to="lab_us-gaap_CashAndCashEquivalentsAtCarryingValue" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="loc_us-gaap_AccountsReceivableNetCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccountsReceivableNetCurrent" xml:lang="en-US">Accounts Receivable, after Allowance for Credit Loss, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_AccountsReceivableNetCurrent" xml:lang="en-US">Accounts receivable</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AccountsReceivableNetCurrent" xml:lang="en-US">Related party accounts receivable</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsReceivableNetCurrent" xlink:to="lab_us-gaap_AccountsReceivableNetCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NotesAndLoansReceivableNetCurrent" xlink:label="loc_us-gaap_NotesAndLoansReceivableNetCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NotesAndLoansReceivableNetCurrent" xml:lang="en-US">Financing Receivable, after Allowance for Credit Loss, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_NotesAndLoansReceivableNetCurrent" xml:lang="en-US">Related party notes receivable&#8212;current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NotesAndLoansReceivableNetCurrent" xml:lang="en-US">Related party notes receivable&#8212;current</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NotesAndLoansReceivableNetCurrent" xlink:to="lab_us-gaap_NotesAndLoansReceivableNetCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerAssetNetCurrent" xlink:label="loc_us-gaap_ContractWithCustomerAssetNetCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ContractWithCustomerAssetNetCurrent" xml:lang="en-US">Contract with Customer, Asset, after Allowance for Credit Loss, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ContractWithCustomerAssetNetCurrent" xml:lang="en-US">Contract assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ContractWithCustomerAssetNetCurrent" xlink:to="lab_us-gaap_ContractWithCustomerAssetNetCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryNet" xlink:label="loc_us-gaap_InventoryNet" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InventoryNet" xml:lang="en-US">Inventory, Net</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_InventoryNet" xml:lang="en-US">Inventories, net</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_InventoryNet" xml:lang="en-US">Inventories, net</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryNet" xlink:to="lab_us-gaap_InventoryNet" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherReceivablesNetCurrent" xlink:label="loc_us-gaap_OtherReceivablesNetCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherReceivablesNetCurrent" xml:lang="en-US">Other Receivables, Net, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherReceivablesNetCurrent" xml:lang="en-US">Other current receivables</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherReceivablesNetCurrent" xlink:to="lab_us-gaap_OtherReceivablesNetCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:label="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xml:lang="en-US">Prepaid Expense and Other Assets, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xml:lang="en-US">Prepaids and other current assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PrepaidExpenseAndOtherAssetsCurrent" xlink:to="lab_us-gaap_PrepaidExpenseAndOtherAssetsCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaap_AssetsCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AssetsCurrent" xml:lang="en-US">Assets, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_AssetsCurrent" xml:lang="en-US">Total current assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsCurrent" xlink:to="lab_us-gaap_AssetsCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentNet" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentNet" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet" xml:lang="en-US">Property, Plant, and Equipment, after Accumulated Depreciation, Depletion, and Amortization</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet" xml:lang="en-US">Property, plant and equipment, net of accumulated depreciation of $76,391 and $67,372, respectively</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentNet" xml:lang="en-US">Property, plant and equipment, net</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentNet" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentNet" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Goodwill" xlink:label="loc_us-gaap_Goodwill" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_Goodwill" xml:lang="en-US">Goodwill</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_Goodwill" xml:lang="en-US">Goodwill</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_Goodwill" xml:lang="en-US">Goodwill acquired</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_Goodwill" xml:lang="en-US">Balance at Beginning</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_Goodwill" xml:lang="en-US">Balance at Ending</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Goodwill" xlink:to="lab_us-gaap_Goodwill" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsNet" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsNet" xml:lang="en-US">Intangible Asset, Finite-Lived, after Accumulated Amortization</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsNet" xml:lang="en-US">Customer relationships, net of accumulated amortization of $50,254 and $46,299, respectively</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsNet" xml:lang="en-US">Net carrying amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsNet" xml:lang="en-US">Total</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsNet" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsNet" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NotesAndLoansReceivableNetNoncurrent" xlink:label="loc_us-gaap_NotesAndLoansReceivableNetNoncurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NotesAndLoansReceivableNetNoncurrent" xml:lang="en-US">Financing Receivable, after Allowance for Credit Loss, Noncurrent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NotesAndLoansReceivableNetNoncurrent" xml:lang="en-US">Related party note receivable</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NotesAndLoansReceivableNetNoncurrent" xlink:to="lab_us-gaap_NotesAndLoansReceivableNetNoncurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseRightOfUseAsset" xlink:label="loc_us-gaap_OperatingLeaseRightOfUseAsset" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingLeaseRightOfUseAsset" xml:lang="en-US">Operating Lease, Right-of-Use Asset</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_OperatingLeaseRightOfUseAsset" xml:lang="en-US">Right-of-use assets</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/definitionGuidance" xlink:label="lab_us-gaap_OperatingLeaseRightOfUseAsset" xml:lang="en-US">Operating Lease, Right-of-Use Asset</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OperatingLeaseRightOfUseAsset" xml:lang="en-US">Operating lease assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeaseRightOfUseAsset" xlink:to="lab_us-gaap_OperatingLeaseRightOfUseAsset" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="loc_us-gaap_OtherAssetsNoncurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherAssetsNoncurrent" xml:lang="en-US">Other Assets, Noncurrent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherAssetsNoncurrent" xml:lang="en-US">Other assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherAssetsNoncurrent" xlink:to="lab_us-gaap_OtherAssetsNoncurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Assets" xlink:label="loc_us-gaap_Assets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_Assets" xml:lang="en-US">Assets</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_Assets" xml:lang="en-US">Total assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Assets" xlink:to="lab_us-gaap_Assets" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract" xml:lang="en-US">Liabilities and Equity [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract" xml:lang="en-US">Liabilities and equity</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:to="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="loc_us-gaap_LiabilitiesCurrentAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LiabilitiesCurrentAbstract" xml:lang="en-US">Liabilities, Current [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LiabilitiesCurrentAbstract" xml:lang="en-US">Current liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract" xlink:to="lab_us-gaap_LiabilitiesCurrentAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableCurrent" xlink:label="loc_us-gaap_AccountsPayableCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccountsPayableCurrent" xml:lang="en-US">Accounts Payable, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_AccountsPayableCurrent" xml:lang="en-US">Accounts payable</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AccountsPayableCurrent" xml:lang="en-US">Accounts payable&#8212;related party</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsPayableCurrent" xlink:to="lab_us-gaap_AccountsPayableCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtCurrent" xlink:label="loc_us-gaap_LongTermDebtCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LongTermDebtCurrent" xml:lang="en-US">Long-Term Debt, Current Maturities</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LongTermDebtCurrent" xml:lang="en-US">Current portion of long-term debt, net</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_LongTermDebtCurrent" xml:lang="en-US">Current debt, net</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtCurrent" xlink:to="lab_us-gaap_LongTermDebtCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerLiabilityCurrent" xlink:label="loc_us-gaap_ContractWithCustomerLiabilityCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ContractWithCustomerLiabilityCurrent" xml:lang="en-US">Contract with Customer, Liability, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ContractWithCustomerLiabilityCurrent" xml:lang="en-US">Contract liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ContractWithCustomerLiabilityCurrent" xlink:to="lab_us-gaap_ContractWithCustomerLiabilityCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccruedLiabilitiesCurrent" xml:lang="en-US">Accrued Liabilities, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AccruedLiabilitiesCurrent" xml:lang="en-US">Accrued expenses</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_AccruedLiabilitiesCurrent" xml:lang="en-US">Accrued expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent" xlink:to="lab_us-gaap_AccruedLiabilitiesCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="loc_us-gaap_OtherLiabilitiesCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherLiabilitiesCurrent" xml:lang="en-US">Other Liabilities, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherLiabilitiesCurrent" xml:lang="en-US">Other current liabilities</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_OtherLiabilitiesCurrent" xml:lang="en-US">Other current liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherLiabilitiesCurrent" xlink:to="lab_us-gaap_OtherLiabilitiesCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaap_LiabilitiesCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LiabilitiesCurrent" xml:lang="en-US">Liabilities, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_LiabilitiesCurrent" xml:lang="en-US">Total current liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesCurrent" xlink:to="lab_us-gaap_LiabilitiesCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="loc_us-gaap_LongTermDebtNoncurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LongTermDebtNoncurrent" xml:lang="en-US">Long-Term Debt, Excluding Current Maturities</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LongTermDebtNoncurrent" xml:lang="en-US">Long-term debt, net</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_LongTermDebtNoncurrent" xml:lang="en-US">Long-term debt, net&#8212;related party</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtNoncurrent" xlink:to="lab_us-gaap_LongTermDebtNoncurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:label="loc_us-gaap_OperatingLeaseLiabilityNoncurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingLeaseLiabilityNoncurrent" xml:lang="en-US">Operating Lease, Liability, Noncurrent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OperatingLeaseLiabilityNoncurrent" xml:lang="en-US">Non-current operating lease liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeaseLiabilityNoncurrent" xlink:to="lab_us-gaap_OperatingLeaseLiabilityNoncurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="loc_us-gaap_OtherLiabilitiesNoncurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherLiabilitiesNoncurrent" xml:lang="en-US">Other Liabilities, Noncurrent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_OtherLiabilitiesNoncurrent" xml:lang="en-US">Other liabilities</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_OtherLiabilitiesNoncurrent" xml:lang="en-US">Total</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherLiabilitiesNoncurrent" xml:lang="en-US">Other liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherLiabilitiesNoncurrent" xlink:to="lab_us-gaap_OtherLiabilitiesNoncurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Liabilities" xlink:label="loc_us-gaap_Liabilities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_Liabilities" xml:lang="en-US">Liabilities</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_Liabilities" xml:lang="en-US">Total liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Liabilities" xlink:to="lab_us-gaap_Liabilities" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract" xml:lang="en-US">Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract" xml:lang="en-US">Shareholders' equity</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract" xlink:to="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MembersEquity" xlink:label="loc_us-gaap_MembersEquity" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MembersEquity" xml:lang="en-US">Members' Equity</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_MembersEquity" xml:lang="en-US">Members' equity</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MembersEquity" xlink:to="lab_us-gaap_MembersEquity" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaap_CommonStockValue" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonStockValue" xml:lang="en-US">Common Stock, Value, Issued</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CommonStockValue" xml:lang="en-US">Common stock, value, issued</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockValue" xlink:to="lab_us-gaap_CommonStockValue" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapital" xlink:label="loc_us-gaap_AdditionalPaidInCapital" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AdditionalPaidInCapital" xml:lang="en-US">Additional Paid in Capital</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AdditionalPaidInCapital" xml:lang="en-US">Additional paid-in capital</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdditionalPaidInCapital" xlink:to="lab_us-gaap_AdditionalPaidInCapital" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_RetainedEarning" xlink:label="loc_hmh_RetainedEarning" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_RetainedEarning" xml:lang="en-US">Retained Earning</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_RetainedEarning" xml:lang="en-US">Retained earnings</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_RetainedEarning" xlink:to="lab_hmh_RetainedEarning" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_RetainedEarning" xml:lang="en-US">Retained earning.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AccumulatedOtherComprehensiveIncomeLoss" xlink:label="loc_hmh_AccumulatedOtherComprehensiveIncomeLoss" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AccumulatedOtherComprehensiveIncomeLoss" xml:lang="en-US">Accumulated Other Comprehensive Income (Loss)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_AccumulatedOtherComprehensiveIncomeLoss" xml:lang="en-US">Accumulated other comprehensive income (loss)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AccumulatedOtherComprehensiveIncomeLoss" xlink:to="lab_hmh_AccumulatedOtherComprehensiveIncomeLoss" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AccumulatedOtherComprehensiveIncomeLoss" xml:lang="en-US">Accumulated other comprehensive income (loss)</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonValue" xlink:label="loc_us-gaap_TreasuryStockCommonValue" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TreasuryStockCommonValue" xml:lang="en-US">Treasury Stock, Common, Value</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_TreasuryStockCommonValue" xml:lang="en-US">Class A common stock held in treasury (254,232 shares as of June 30, 2026)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockCommonValue" xlink:to="lab_us-gaap_TreasuryStockCommonValue" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquity" xlink:label="loc_us-gaap_StockholdersEquity" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockholdersEquity" xml:lang="en-US">Equity, Attributable to Parent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_StockholdersEquity" xml:lang="en-US">Total shareholders' equity</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquity" xlink:to="lab_us-gaap_StockholdersEquity" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterest" xlink:label="loc_us-gaap_MinorityInterest" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MinorityInterest" xml:lang="en-US">Equity, Attributable to Noncontrolling Interest</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_MinorityInterest" xml:lang="en-US">Non-controlling interests</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MinorityInterest" xlink:to="lab_us-gaap_MinorityInterest" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xml:lang="en-US">Equity, Including Portion Attributable to Noncontrolling Interest</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xml:lang="en-US">Total equity</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xml:lang="en-US">Beginning balance</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xml:lang="en-US">Ending balance</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xml:lang="en-US">Total</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" xlink:to="lab_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="loc_us-gaap_LiabilitiesAndStockholdersEquity" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquity" xml:lang="en-US">Liabilities and Equity</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquity" xml:lang="en-US">Total liabilities and shareholders' equity</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity" xlink:to="lab_us-gaap_LiabilitiesAndStockholdersEquity" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent" xlink:label="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent" xml:lang="en-US">Accounts Receivable, Allowance for Credit Loss, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent" xml:lang="en-US">Accounts receivable allowance</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent" xlink:to="lab_us-gaap_AllowanceForDoubtfulAccountsReceivableCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:label="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xml:lang="en-US">Property, Plant, and Equipment, Accumulated Depreciation, Depletion, and Amortization</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xml:lang="en-US">Property, plant and equipment, accumulated depreciation</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xml:lang="en-US">Less: Accumulated depreciation</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" xlink:to="lab_us-gaap_AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xml:lang="en-US">Intangible Asset, Finite-Lived, Accumulated Amortization</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xml:lang="en-US">Intangible assets, accumulated amortization</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xml:lang="en-US">Accumulated amortization</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonStockParOrStatedValuePerShare" xml:lang="en-US">Common Stock, Par or Stated Value Per Share</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CommonStockParOrStatedValuePerShare" xml:lang="en-US">Common stock, par value (in usd per share)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockParOrStatedValuePerShare" xlink:to="lab_us-gaap_CommonStockParOrStatedValuePerShare" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="loc_us-gaap_CommonStockSharesAuthorized" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonStockSharesAuthorized" xml:lang="en-US">Common Stock, Shares Authorized</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CommonStockSharesAuthorized" xml:lang="en-US">Common stock, shares authorized (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesAuthorized" xlink:to="lab_us-gaap_CommonStockSharesAuthorized" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaap_CommonStockSharesIssued" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonStockSharesIssued" xml:lang="en-US">Common Stock, Shares, Issued</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CommonStockSharesIssued" xml:lang="en-US">Common stock, shares issued (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesIssued" xlink:to="lab_us-gaap_CommonStockSharesIssued" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaap_CommonStockSharesOutstanding" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonStockSharesOutstanding" xml:lang="en-US">Common Stock, Shares, Outstanding</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CommonStockSharesOutstanding" xml:lang="en-US">Common stock, shares outstanding (in shares)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_CommonStockSharesOutstanding" xml:lang="en-US">Beginning balance, shares outstanding (in shares)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_CommonStockSharesOutstanding" xml:lang="en-US">Ending balance, shares outstanding (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesOutstanding" xlink:to="lab_us-gaap_CommonStockSharesOutstanding" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonShares" xlink:label="loc_us-gaap_TreasuryStockCommonShares" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TreasuryStockCommonShares" xml:lang="en-US">Treasury Stock, Common, Shares</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_TreasuryStockCommonShares" xml:lang="en-US">Treasury stock (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockCommonShares" xlink:to="lab_us-gaap_TreasuryStockCommonShares" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfStockholdersEquityAbstract" xlink:label="loc_us-gaap_StatementOfStockholdersEquityAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StatementOfStockholdersEquityAbstract" xml:lang="en-US">Statement of Stockholders' Equity [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfStockholdersEquityAbstract" xlink:to="lab_us-gaap_StatementOfStockholdersEquityAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StatementEquityComponentsAxis" xml:lang="en-US">Equity Components [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StatementEquityComponentsAxis" xml:lang="en-US">Equity Components [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementEquityComponentsAxis" xlink:to="lab_us-gaap_StatementEquityComponentsAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EquityComponentDomain" xml:lang="en-US">Equity Component [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_EquityComponentDomain" xml:lang="en-US">Equity Component [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquityComponentDomain" xlink:to="lab_us-gaap_EquityComponentDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonStockMember" xml:lang="en-US">Common Stock [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CommonStockMember" xml:lang="en-US">Common Stock</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockMember" xlink:to="lab_us-gaap_CommonStockMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AdditionalPaidInCapitalMember" xml:lang="en-US">Additional Paid-in Capital [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AdditionalPaidInCapitalMember" xml:lang="en-US">Additional paid-in capital</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdditionalPaidInCapitalMember" xlink:to="lab_us-gaap_AdditionalPaidInCapitalMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember" xml:lang="en-US">AOCI Attributable to Parent [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember" xml:lang="en-US">Accumulated other comprehensive income (loss)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember" xlink:to="lab_us-gaap_AccumulatedOtherComprehensiveIncomeMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockCommonMember" xlink:label="loc_us-gaap_TreasuryStockCommonMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TreasuryStockCommonMember" xml:lang="en-US">Treasury Stock, Common [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_TreasuryStockCommonMember" xml:lang="en-US">Common stock held in treasury</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockCommonMember" xlink:to="lab_us-gaap_TreasuryStockCommonMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RetainedEarningsMember" xml:lang="en-US">Retained Earnings [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RetainedEarningsMember" xml:lang="en-US">Retained earnings (loss)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetainedEarningsMember" xlink:to="lab_us-gaap_RetainedEarningsMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NoncontrollingInterestMember" xlink:label="loc_us-gaap_NoncontrollingInterestMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NoncontrollingInterestMember" xml:lang="en-US">Noncontrolling Interest [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NoncontrollingInterestMember" xml:lang="en-US">Non-controlling interest</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoncontrollingInterestMember" xlink:to="lab_us-gaap_NoncontrollingInterestMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_HedgingReserveMember" xlink:label="loc_hmh_HedgingReserveMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_HedgingReserveMember" xml:lang="en-US">Hedging Reserve [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_HedgingReserveMember" xlink:to="lab_hmh_HedgingReserveMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_PensionRemeasurementReserveMember" xlink:label="loc_hmh_PensionRemeasurementReserveMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_PensionRemeasurementReserveMember" xml:lang="en-US">Pension Remeasurement Reserve [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_PensionRemeasurementReserveMember" xlink:to="lab_hmh_PensionRemeasurementReserveMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_CurrencyTranslationReserveMember" xlink:label="loc_hmh_CurrencyTranslationReserveMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_CurrencyTranslationReserveMember" xml:lang="en-US">Currency Translation Reserve [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_CurrencyTranslationReserveMember" xlink:to="lab_hmh_CurrencyTranslationReserveMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xml:lang="en-US">Increase (Decrease) in Stockholders' Equity [Roll Forward]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xml:lang="en-US">Increase (Decrease) in Stockholders' Equity [Roll Forward]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xml:lang="en-US">Stock Issued During Period, Shares, New Issues</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/definitionGuidance" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xml:lang="en-US">Issuance of common stock in initial public offering, net of offering costs (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesNewIssues" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues" xml:lang="en-US">Stock Issued During Period, Value, New Issues</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues" xml:lang="en-US">Issuance of common stock in initial public offering, net of offering costs</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:to="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodShares" xlink:label="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares" xml:lang="en-US">Stock Repurchased and Retired During Period, Shares</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares" xml:lang="en-US">Redemption under exchange agreement with Principal Stockholders (in shares)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares" xml:lang="en-US">Shares repurchased (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares" xlink:to="lab_us-gaap_StockRepurchasedAndRetiredDuringPeriodShares" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchasedAndRetiredDuringPeriodValue" xlink:label="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue" xml:lang="en-US">Stock Repurchased and Retired During Period, Value</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue" xml:lang="en-US">Redemption under exchange agreement with Principal Stockholders</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue" xml:lang="en-US">Shares repurchased</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue" xlink:to="lab_us-gaap_StockRepurchasedAndRetiredDuringPeriodValue" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AdjustmentsToAdditionalPaidInCapitalPurchaseOfShares" xlink:label="loc_hmh_AdjustmentsToAdditionalPaidInCapitalPurchaseOfShares" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AdjustmentsToAdditionalPaidInCapitalPurchaseOfShares" xml:lang="en-US">Adjustments To Additional Paid In Capital, Purchase Of Shares</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_hmh_AdjustmentsToAdditionalPaidInCapitalPurchaseOfShares" xml:lang="en-US">Purchase of HMH B.V. voting shares from Principal Stockholders</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_AdjustmentsToAdditionalPaidInCapitalPurchaseOfShares" xml:lang="en-US">Purchase of HMH B.V. voting shares from Principal Stockholders</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AdjustmentsToAdditionalPaidInCapitalPurchaseOfShares" xlink:to="lab_hmh_AdjustmentsToAdditionalPaidInCapitalPurchaseOfShares" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AdjustmentsToAdditionalPaidInCapitalPurchaseOfShares" xml:lang="en-US">Adjustments To Additional Paid In Capital, Purchase Of Shares</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuanceNet" xlink:label="loc_hmh_NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuanceNet" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuanceNet" xml:lang="en-US">Noncontrolling Interest, Increase from Subsidiary Equity Issuance, Net</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuanceNet" xml:lang="en-US">Effect of the Corporate Reorganization Transactions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuanceNet" xlink:to="lab_hmh_NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuanceNet" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuanceNet" xml:lang="en-US">Noncontrolling Interest, Increase from Subsidiary Equity Issuance, Net</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts" xml:lang="en-US">Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts" xml:lang="en-US">IPO related costs</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts" xlink:to="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalStockIssuedIssuanceCosts" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiabilityAndTaxImpactOfReorganization" xlink:label="loc_hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiabilityAndTaxImpactOfReorganization" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiabilityAndTaxImpactOfReorganization" xml:lang="en-US">Adjustments To Additional Paid In Capital, Tax Receivable Agreement Liability And Tax Impact Of Reorganization</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiabilityAndTaxImpactOfReorganization" xml:lang="en-US">TRA liability and related deferred tax impact from the Corporate Reorganization Transactions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiabilityAndTaxImpactOfReorganization" xlink:to="lab_hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiabilityAndTaxImpactOfReorganization" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiabilityAndTaxImpactOfReorganization" xml:lang="en-US">Adjustments To Additional Paid In Capital, Tax Receivable Agreement Liability And Tax Impact Of Reorganization</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xml:lang="en-US">Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xml:lang="en-US">Share-based compensation (in shares)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xml:lang="en-US">Equity-based compensation (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xml:lang="en-US">Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xml:lang="en-US">Share-based compensation</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xml:lang="en-US">Share-based payment arrangement, after forfeiture</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:to="lab_us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TreasuryStockValueAcquiredCostMethod" xml:lang="en-US">Treasury Stock, Value, Acquired, Cost Method</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_TreasuryStockValueAcquiredCostMethod" xml:lang="en-US">Purchase of treasury stock</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TreasuryStockValueAcquiredCostMethod" xlink:to="lab_us-gaap_TreasuryStockValueAcquiredCostMethod" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_SaleOwnershipInterestInNonControllingInterest" xlink:label="loc_hmh_SaleOwnershipInterestInNonControllingInterest" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_SaleOwnershipInterestInNonControllingInterest" xml:lang="en-US">Sale Ownership Interest In Non Controlling Interest</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_SaleOwnershipInterestInNonControllingInterest" xml:lang="en-US">Sale ownership interest in Hydril Arabia</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_SaleOwnershipInterestInNonControllingInterest" xlink:to="lab_hmh_SaleOwnershipInterestInNonControllingInterest" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_SaleOwnershipInterestInNonControllingInterest" xml:lang="en-US">Sale ownership interest in non controlling interest.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OtherComprehensiveIncomePriorToReorganizationTransactions" xlink:label="loc_hmh_OtherComprehensiveIncomePriorToReorganizationTransactions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OtherComprehensiveIncomePriorToReorganizationTransactions" xml:lang="en-US">Other Comprehensive Income Prior To Reorganization Transactions</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_OtherComprehensiveIncomePriorToReorganizationTransactions" xml:lang="en-US">Other comprehensive income prior to the Corporate Reorganization Transactions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OtherComprehensiveIncomePriorToReorganizationTransactions" xlink:to="lab_hmh_OtherComprehensiveIncomePriorToReorganizationTransactions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_OtherComprehensiveIncomePriorToReorganizationTransactions" xml:lang="en-US">Other comprehensive income prior to reorganization transactions.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_NetIncomePriorToTheCorporateReorganizationTransactions" xlink:label="loc_hmh_NetIncomePriorToTheCorporateReorganizationTransactions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_NetIncomePriorToTheCorporateReorganizationTransactions" xml:lang="en-US">Net income Prior To The Corporate Reorganization Transactions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_NetIncomePriorToTheCorporateReorganizationTransactions" xlink:to="lab_hmh_NetIncomePriorToTheCorporateReorganizationTransactions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_NetIncomePriorToTheCorporateReorganizationTransactions" xml:lang="en-US">Net income prior to the corporate reorganization transactions.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_NetIncomeLossSubsequentToTheCorporateReorganizationTransactions" xlink:label="loc_hmh_NetIncomeLossSubsequentToTheCorporateReorganizationTransactions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_NetIncomeLossSubsequentToTheCorporateReorganizationTransactions" xml:lang="en-US">Net Income (Loss) Subsequent To The Corporate Reorganization Transactions</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_NetIncomeLossSubsequentToTheCorporateReorganizationTransactions" xml:lang="en-US">Net income (loss) subsequent to the Corporate Reorganization Transactions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_NetIncomeLossSubsequentToTheCorporateReorganizationTransactions" xlink:to="lab_hmh_NetIncomeLossSubsequentToTheCorporateReorganizationTransactions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_NetIncomeLossSubsequentToTheCorporateReorganizationTransactions" xml:lang="en-US">Net income (loss) subsequent to the corporate reorganization transactions.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OtherComprehensiveIncomeSubsequentToTheCorporateReorganizationTransactions" xlink:label="loc_hmh_OtherComprehensiveIncomeSubsequentToTheCorporateReorganizationTransactions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OtherComprehensiveIncomeSubsequentToTheCorporateReorganizationTransactions" xml:lang="en-US">Other Comprehensive Income Subsequent To The Corporate Reorganization Transactions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OtherComprehensiveIncomeSubsequentToTheCorporateReorganizationTransactions" xlink:to="lab_hmh_OtherComprehensiveIncomeSubsequentToTheCorporateReorganizationTransactions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_OtherComprehensiveIncomeSubsequentToTheCorporateReorganizationTransactions" xml:lang="en-US">Other comprehensive income subsequent to the corporate reorganization transactions.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfCashFlowsAbstract" xlink:label="loc_us-gaap_StatementOfCashFlowsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StatementOfCashFlowsAbstract" xml:lang="en-US">Statement of Cash Flows [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract" xlink:to="lab_us-gaap_StatementOfCashFlowsAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xml:lang="en-US">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xml:lang="en-US">Cash flows from operating activities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:to="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xml:lang="en-US">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xml:lang="en-US">Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:to="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationDepletionAndAmortization" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DepreciationDepletionAndAmortization" xml:lang="en-US">Depreciation, Depletion and Amortization</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DepreciationDepletionAndAmortization" xml:lang="en-US">Depreciation and amortization</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DepreciationDepletionAndAmortization" xlink:to="lab_us-gaap_DepreciationDepletionAndAmortization" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensation" xlink:label="loc_us-gaap_ShareBasedCompensation" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensation" xml:lang="en-US">Share-Based Payment Arrangement, Noncash Expense</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensation" xml:lang="en-US">Share-based compensation expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensation" xlink:to="lab_us-gaap_ShareBasedCompensation" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AmortizationOfFinancingCosts" xlink:label="loc_us-gaap_AmortizationOfFinancingCosts" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AmortizationOfFinancingCosts" xml:lang="en-US">Amortization of Debt Issuance Costs</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AmortizationOfFinancingCosts" xml:lang="en-US">Amortization of borrowing costs</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AmortizationOfFinancingCosts" xlink:to="lab_us-gaap_AmortizationOfFinancingCosts" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringCosts" xlink:label="loc_us-gaap_RestructuringCosts" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RestructuringCosts" xml:lang="en-US">Restructuring Costs</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RestructuringCosts" xml:lang="en-US">Restructuring and other expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringCosts" xlink:to="lab_us-gaap_RestructuringCosts" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredIncomeTaxExpenseBenefit" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredIncomeTaxExpenseBenefit" xml:lang="en-US">Deferred Income Tax Expense (Benefit)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredIncomeTaxExpenseBenefit" xml:lang="en-US">Deferred tax expense (benefit)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:label="lab_us-gaap_DeferredIncomeTaxExpenseBenefit" xml:lang="en-US">Total deferred tax expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:to="lab_us-gaap_DeferredIncomeTaxExpenseBenefit" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaidInKindInterest" xlink:label="loc_us-gaap_PaidInKindInterest" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PaidInKindInterest" xml:lang="en-US">Paid-in-Kind Interest</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PaidInKindInterest" xml:lang="en-US">Payment-in-kind interest</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaidInKindInterest" xlink:to="lab_us-gaap_PaidInKindInterest" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProvisionForDoubtfulAccounts" xlink:label="loc_us-gaap_ProvisionForDoubtfulAccounts" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProvisionForDoubtfulAccounts" xml:lang="en-US">Accounts Receivable, Credit Loss Expense (Reversal)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ProvisionForDoubtfulAccounts" xml:lang="en-US">Provision for bad debt expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProvisionForDoubtfulAccounts" xlink:to="lab_us-gaap_ProvisionForDoubtfulAccounts" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryWriteDown" xlink:label="loc_us-gaap_InventoryWriteDown" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InventoryWriteDown" xml:lang="en-US">Inventory Write-down</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_InventoryWriteDown" xml:lang="en-US">Provision for inventory write-down</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryWriteDown" xlink:to="lab_us-gaap_InventoryWriteDown" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xml:lang="en-US">Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xml:lang="en-US">Changes in operating assets and liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:to="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsReceivable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsReceivable" xml:lang="en-US">Increase (Decrease) in Accounts Receivable</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsReceivable" xml:lang="en-US">Accounts receivable and related party accounts receivable</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:to="lab_us-gaap_IncreaseDecreaseInAccountsReceivable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerAsset" xlink:label="loc_us-gaap_IncreaseDecreaseInContractWithCustomerAsset" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInContractWithCustomerAsset" xml:lang="en-US">Increase (Decrease) in Contract with Customer, Asset</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInContractWithCustomerAsset" xml:lang="en-US">Contract assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInContractWithCustomerAsset" xlink:to="lab_us-gaap_IncreaseDecreaseInContractWithCustomerAsset" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInInventories" xlink:label="loc_us-gaap_IncreaseDecreaseInInventories" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInInventories" xml:lang="en-US">Increase (Decrease) in Inventories</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInInventories" xml:lang="en-US">Inventories, net</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInInventories" xlink:to="lab_us-gaap_IncreaseDecreaseInInventories" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherReceivables" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherReceivables" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherReceivables" xml:lang="en-US">Increase (Decrease) in Other Receivables</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherReceivables" xml:lang="en-US">Other current receivables</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInOtherReceivables" xlink:to="lab_us-gaap_IncreaseDecreaseInOtherReceivables" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xml:lang="en-US">Increase (Decrease) in Prepaid Expense and Other Assets</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xml:lang="en-US">Prepaid and other current assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" xlink:to="lab_us-gaap_IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccountsPayable" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsPayable" xml:lang="en-US">Increase (Decrease) in Accounts Payable</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsPayable" xml:lang="en-US">Accounts payable and accounts payable&#8212;related party</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInAccountsPayable" xlink:to="lab_us-gaap_IncreaseDecreaseInAccountsPayable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInAccruedLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInAccruedLiabilities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities" xml:lang="en-US">Increase (Decrease) in Accrued Liabilities</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities" xml:lang="en-US">Accrued expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInAccruedLiabilities" xlink:to="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInContractWithCustomerLiability" xlink:label="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInContractWithCustomerLiability" xml:lang="en-US">Increase (Decrease) in Contract with Customer, Liability</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInContractWithCustomerLiability" xml:lang="en-US">Contract liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInContractWithCustomerLiability" xlink:to="lab_us-gaap_IncreaseDecreaseInContractWithCustomerLiability" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherOperatingLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities" xml:lang="en-US">Increase (Decrease) in Other Operating Liabilities</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities" xml:lang="en-US">Other current and long-term liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities" xlink:to="lab_us-gaap_IncreaseDecreaseInOtherOperatingLiabilities" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet" xml:lang="en-US">Increase (Decrease) in Other Operating Assets and Liabilities, Net</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet" xml:lang="en-US">Other, net</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet" xlink:to="lab_us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ExtinguishmentOfDebtAmount" xlink:label="loc_us-gaap_ExtinguishmentOfDebtAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ExtinguishmentOfDebtAmount" xml:lang="en-US">Extinguishment of Debt, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ExtinguishmentOfDebtAmount" xml:lang="en-US">Loss on debt extinguishment</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ExtinguishmentOfDebtAmount" xlink:to="lab_us-gaap_ExtinguishmentOfDebtAmount" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities" xml:lang="en-US">Cash Provided by (Used in) Operating Activity, Including Discontinued Operation</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities" xml:lang="en-US">Net cash provided by (used in) operating activities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:to="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xml:lang="en-US">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xml:lang="en-US">Cash flows from investing activities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:to="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xml:lang="en-US">Payments to Acquire Property, Plant, and Equipment</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xml:lang="en-US">Purchase of property, plant and equipment</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" xlink:to="lab_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_PaymentsForDevelopmentCosts" xlink:label="loc_hmh_PaymentsForDevelopmentCosts" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_PaymentsForDevelopmentCosts" xml:lang="en-US">Payments For Development Costs</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_hmh_PaymentsForDevelopmentCosts" xml:lang="en-US">Development costs</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_PaymentsForDevelopmentCosts" xlink:to="lab_hmh_PaymentsForDevelopmentCosts" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_PaymentsForDevelopmentCosts" xml:lang="en-US">Payments For Development Costs</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired" xml:lang="en-US">Payments to Acquire Businesses, Net of Cash Acquired</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired" xml:lang="en-US">Acquisition of business, net of cash</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired" xlink:to="lab_us-gaap_PaymentsToAcquireBusinessesNetOfCashAcquired" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities" xml:lang="en-US">Cash Provided by (Used in) Investing Activity, Including Discontinued Operation</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities" xml:lang="en-US">Net cash provided by (used in) investing activities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:to="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:label="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xml:lang="en-US">Proceeds from Sale of Property, Plant, and Equipment</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xml:lang="en-US">Purchase of property, plant and equipment</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" xlink:to="lab_us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireIntangibleAssets" xlink:label="loc_us-gaap_PaymentsToAcquireIntangibleAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PaymentsToAcquireIntangibleAssets" xml:lang="en-US">Payments to Acquire Intangible Assets</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_PaymentsToAcquireIntangibleAssets" xml:lang="en-US">Purchase of intangible asset</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquireIntangibleAssets" xlink:to="lab_us-gaap_PaymentsToAcquireIntangibleAssets" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xml:lang="en-US">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xml:lang="en-US">Cash flows from financing activities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:to="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfCommonStock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfCommonStock" xml:lang="en-US">Proceeds from Issuance of Common Stock</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfCommonStock" xml:lang="en-US">Issuance of common stock in initial public offering (IPO), net of underwriting discount</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:to="lab_us-gaap_ProceedsFromIssuanceOfCommonStock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForRepurchaseOfPrivatePlacement" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfPrivatePlacement" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PaymentsForRepurchaseOfPrivatePlacement" xml:lang="en-US">Payments for Repurchase of Private Placement</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_PaymentsForRepurchaseOfPrivatePlacement" xml:lang="en-US">Purchase of HMH B.V. voting shares from Principal Stockholders</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsForRepurchaseOfPrivatePlacement" xlink:to="lab_us-gaap_PaymentsForRepurchaseOfPrivatePlacement" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForRepurchaseOfInitialPublicOffering" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfInitialPublicOffering" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PaymentsForRepurchaseOfInitialPublicOffering" xml:lang="en-US">Payments for Repurchase of Initial Public Offering</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_PaymentsForRepurchaseOfInitialPublicOffering" xml:lang="en-US">Redemption under exchange agreement with Principal Stockholders</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsForRepurchaseOfInitialPublicOffering" xlink:to="lab_us-gaap_PaymentsForRepurchaseOfInitialPublicOffering" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsOfStockIssuanceCosts" xlink:label="loc_us-gaap_PaymentsOfStockIssuanceCosts" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PaymentsOfStockIssuanceCosts" xml:lang="en-US">Payments of Stock Issuance Costs</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_PaymentsOfStockIssuanceCosts" xml:lang="en-US">IPO issuance costs</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PaymentsOfStockIssuanceCosts" xml:lang="en-US">Stock issuance costs</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsOfStockIssuanceCosts" xlink:to="lab_us-gaap_PaymentsOfStockIssuanceCosts" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfRelatedPartyDebt" xlink:label="loc_us-gaap_RepaymentsOfRelatedPartyDebt" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RepaymentsOfRelatedPartyDebt" xml:lang="en-US">Repayments of Related Party Debt</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_RepaymentsOfRelatedPartyDebt" xml:lang="en-US">Repayment of long-term debt, net&#8212;related party</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RepaymentsOfRelatedPartyDebt" xlink:to="lab_us-gaap_RepaymentsOfRelatedPartyDebt" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromLongTermLinesOfCredit" xlink:label="loc_us-gaap_ProceedsFromLongTermLinesOfCredit" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProceedsFromLongTermLinesOfCredit" xml:lang="en-US">Proceeds from Long-Term Lines of Credit</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ProceedsFromLongTermLinesOfCredit" xml:lang="en-US">Proceeds from issuance of long-term loans&#8212;revolving credit facilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromLongTermLinesOfCredit" xlink:to="lab_us-gaap_ProceedsFromLongTermLinesOfCredit" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfLongTermLinesOfCredit" xlink:label="loc_us-gaap_RepaymentsOfLongTermLinesOfCredit" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RepaymentsOfLongTermLinesOfCredit" xml:lang="en-US">Repayments of Long-Term Lines of Credit</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_RepaymentsOfLongTermLinesOfCredit" xml:lang="en-US">Repayment of revolving credit facilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RepaymentsOfLongTermLinesOfCredit" xlink:to="lab_us-gaap_RepaymentsOfLongTermLinesOfCredit" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:label="loc_us-gaap_PaymentsForRepurchaseOfCommonStock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PaymentsForRepurchaseOfCommonStock" xml:lang="en-US">Payments for Repurchase of Common Stock</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_PaymentsForRepurchaseOfCommonStock" xml:lang="en-US">Purchase of treasury shares</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsForRepurchaseOfCommonStock" xlink:to="lab_us-gaap_PaymentsForRepurchaseOfCommonStock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities" xml:lang="en-US">Cash Provided by (Used in) Financing Activity, Including Discontinued Operation</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities" xml:lang="en-US">Net cash provided by (used in) financing activities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:to="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromMinorityShareholders" xlink:label="loc_us-gaap_ProceedsFromMinorityShareholders" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProceedsFromMinorityShareholders" xml:lang="en-US">Proceeds from Noncontrolling Interests</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ProceedsFromMinorityShareholders" xml:lang="en-US">Proceeds from sale to non-controlling interests</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromMinorityShareholders" xlink:to="lab_us-gaap_ProceedsFromMinorityShareholders" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_PaymentOfBorrowingCosts" xlink:label="loc_hmh_PaymentOfBorrowingCosts" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_PaymentOfBorrowingCosts" xml:lang="en-US">Payment Of Borrowing Costs</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_hmh_PaymentOfBorrowingCosts" xml:lang="en-US">Payment of borrowing costs</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_PaymentOfBorrowingCosts" xlink:to="lab_hmh_PaymentOfBorrowingCosts" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_PaymentOfBorrowingCosts" xml:lang="en-US">Payment of borrowing Costs.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromIssuanceOfLongTermDebt" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebt" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfLongTermDebt" xml:lang="en-US">Proceeds from Issuance of Long-Term Debt</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ProceedsFromIssuanceOfLongTermDebt" xml:lang="en-US">Proceeds from issuance of long-term loans&#8212;bonds</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromIssuanceOfLongTermDebt" xlink:to="lab_us-gaap_ProceedsFromIssuanceOfLongTermDebt" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RepaymentsOfLongTermDebt" xlink:label="loc_us-gaap_RepaymentsOfLongTermDebt" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RepaymentsOfLongTermDebt" xml:lang="en-US">Repayments of Long-Term Debt</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_RepaymentsOfLongTermDebt" xml:lang="en-US">Repayment of long-term loans&#8212;bonds</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RepaymentsOfLongTermDebt" xlink:to="lab_us-gaap_RepaymentsOfLongTermDebt" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xlink:label="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xml:lang="en-US">Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xml:lang="en-US">Effect of foreign exchange rate on cash and cash equivalents</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xlink:to="lab_us-gaap_EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xml:lang="en-US">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xml:lang="en-US">Net increase (decrease) in cash and cash equivalents</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xml:lang="en-US">Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xml:lang="en-US">Cash and cash equivalents beginning of period</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xml:lang="en-US">Cash and cash equivalents end of period</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" xlink:to="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SupplementalCashFlowInformationAbstract" xlink:label="loc_us-gaap_SupplementalCashFlowInformationAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SupplementalCashFlowInformationAbstract" xml:lang="en-US">Supplemental Cash Flow Information [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SupplementalCashFlowInformationAbstract" xml:lang="en-US">Supplemental cash flow information:</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SupplementalCashFlowInformationAbstract" xlink:to="lab_us-gaap_SupplementalCashFlowInformationAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxesPaidNet" xlink:label="loc_us-gaap_IncomeTaxesPaidNet" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeTaxesPaidNet" xml:lang="en-US">Income Tax Paid, after Refund Received</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncomeTaxesPaidNet" xml:lang="en-US">Cash paid for income taxes, net</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxesPaidNet" xlink:to="lab_us-gaap_IncomeTaxesPaidNet" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestPaidNet" xlink:label="loc_us-gaap_InterestPaidNet" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InterestPaidNet" xml:lang="en-US">Interest Paid, Excluding Capitalized Interest, Operating Activity</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_InterestPaidNet" xml:lang="en-US">Cash paid for interest</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestPaidNet" xlink:to="lab_us-gaap_InterestPaidNet" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:label="loc_us-gaap_NoncashInvestingAndFinancingItemsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NoncashInvestingAndFinancingItemsAbstract" xml:lang="en-US">Noncash Investing and Financing Items [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NoncashInvestingAndFinancingItemsAbstract" xml:lang="en-US">Supplemental non-cash financing activities:</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:to="lab_us-gaap_NoncashInvestingAndFinancingItemsAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtIssuanceCostsIncurredDuringNoncashOrPartialNoncashTransaction" xlink:label="loc_us-gaap_DebtIssuanceCostsIncurredDuringNoncashOrPartialNoncashTransaction" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtIssuanceCostsIncurredDuringNoncashOrPartialNoncashTransaction" xml:lang="en-US">Debt Issuance Costs Incurred During Noncash or Partial Noncash Transaction</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DebtIssuanceCostsIncurredDuringNoncashOrPartialNoncashTransaction" xml:lang="en-US">Deferred IPO cost netted with IPO proceeds</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtIssuanceCostsIncurredDuringNoncashOrPartialNoncashTransaction" xlink:to="lab_us-gaap_DebtIssuanceCostsIncurredDuringNoncashOrPartialNoncashTransaction" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_SettlementOfLongTermDebtNetRelatedPartyAndAccountsReceivableAndRelatedPartyAccountsReceivable" xlink:label="loc_hmh_SettlementOfLongTermDebtNetRelatedPartyAndAccountsReceivableAndRelatedPartyAccountsReceivable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_SettlementOfLongTermDebtNetRelatedPartyAndAccountsReceivableAndRelatedPartyAccountsReceivable" xml:lang="en-US">Settlement of Long-Term Debt, Net Related Party And Accounts Receivable And Related Party Accounts Receivable</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_SettlementOfLongTermDebtNetRelatedPartyAndAccountsReceivableAndRelatedPartyAccountsReceivable" xml:lang="en-US">Settlement of long-term debt, net &#8212;related party and related party notes receivable</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_SettlementOfLongTermDebtNetRelatedPartyAndAccountsReceivableAndRelatedPartyAccountsReceivable" xlink:to="lab_hmh_SettlementOfLongTermDebtNetRelatedPartyAndAccountsReceivableAndRelatedPartyAccountsReceivable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_SettlementOfLongTermDebtNetRelatedPartyAndAccountsReceivableAndRelatedPartyAccountsReceivable" xml:lang="en-US">Settlement of Long-Term Debt, Net Related Party And Accounts Receivable And Related Party Accounts Receivable</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ContingentConsiderationInConnectionWithAcquisition" xlink:label="loc_hmh_ContingentConsiderationInConnectionWithAcquisition" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ContingentConsiderationInConnectionWithAcquisition" xml:lang="en-US">Contingent Consideration In Connection With Acquisition</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ContingentConsiderationInConnectionWithAcquisition" xlink:to="lab_hmh_ContingentConsiderationInConnectionWithAcquisition" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ContingentConsiderationInConnectionWithAcquisition" xml:lang="en-US">Contingent consideration in connection with acquisition.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:label="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xml:lang="en-US">Organization, Consolidation and Presentation of Financial Statements [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:to="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OrganizationConsolidationAndPresentationOfFinancialStatementsTable" xlink:label="loc_hmh_OrganizationConsolidationAndPresentationOfFinancialStatementsTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OrganizationConsolidationAndPresentationOfFinancialStatementsTable" xml:lang="en-US">Organization Consolidation And Presentation Of Financial Statements [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OrganizationConsolidationAndPresentationOfFinancialStatementsTable" xlink:to="lab_hmh_OrganizationConsolidationAndPresentationOfFinancialStatementsTable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OrganizationConsolidationAndPresentationOfFinancialStatementsLineItems" xlink:label="loc_hmh_OrganizationConsolidationAndPresentationOfFinancialStatementsLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OrganizationConsolidationAndPresentationOfFinancialStatementsLineItems" xml:lang="en-US">Organization Consolidation And Presentation Of Financial Statements [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OrganizationConsolidationAndPresentationOfFinancialStatementsLineItems" xlink:to="lab_hmh_OrganizationConsolidationAndPresentationOfFinancialStatementsLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:label="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xml:lang="en-US">Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xml:lang="en-US">Organization and nature of business</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:to="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccountingPoliciesAbstract" xml:lang="en-US">Accounting Policies [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountingPoliciesAbstract" xlink:to="lab_us-gaap_AccountingPoliciesAbstract" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AccountingPoliciesTable" xlink:label="loc_hmh_AccountingPoliciesTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AccountingPoliciesTable" xml:lang="en-US">Accounting Policies [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AccountingPoliciesTable" xlink:to="lab_hmh_AccountingPoliciesTable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AccountingPoliciesLineItems" xlink:label="loc_hmh_AccountingPoliciesLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AccountingPoliciesLineItems" xml:lang="en-US">Accounting Policies [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AccountingPoliciesLineItems" xlink:to="lab_hmh_AccountingPoliciesLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock" xlink:label="loc_us-gaap_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock" xml:lang="en-US">Basis of Presentation and Significant Accounting Policies [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock" xml:lang="en-US">Basis of presentation and summary of significant accounting policies</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock" xlink:to="lab_us-gaap_BasisOfPresentationAndSignificantAccountingPoliciesTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SignificantAccountingPoliciesTextBlock" xlink:label="loc_us-gaap_SignificantAccountingPoliciesTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SignificantAccountingPoliciesTextBlock" xml:lang="en-US">Significant Accounting Policies [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SignificantAccountingPoliciesTextBlock" xml:lang="en-US">Summary of significant accounting policies</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SignificantAccountingPoliciesTextBlock" xlink:to="lab_us-gaap_SignificantAccountingPoliciesTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationAndAssetAcquisitionAbstract" xlink:label="loc_us-gaap_BusinessCombinationAndAssetAcquisitionAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationAndAssetAcquisitionAbstract" xml:lang="en-US">Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationAndAssetAcquisitionAbstract" xlink:to="lab_us-gaap_BusinessCombinationAndAssetAcquisitionAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xml:lang="en-US">Business Combination [Table]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xml:lang="en-US">Business Combination [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" xlink:to="lab_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionLineItems" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionLineItems" xml:lang="en-US">Business Combination [Line Items]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessAcquisitionLineItems" xml:lang="en-US">Business Combination [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems" xlink:to="lab_us-gaap_BusinessAcquisitionLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationDisclosureTextBlock" xlink:label="loc_us-gaap_BusinessCombinationDisclosureTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationDisclosureTextBlock" xml:lang="en-US">Business Combination [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationDisclosureTextBlock" xml:lang="en-US">Business Combinations</link:label>
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          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_UnauditedProFormaConsolidatedBalanceSheetAbstract" xlink:label="loc_hmh_UnauditedProFormaConsolidatedBalanceSheetAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_UnauditedProFormaConsolidatedBalanceSheetAbstract" xml:lang="en-US">Unaudited Pro Forma Consolidated Balance Sheet [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_UnauditedProFormaConsolidatedBalanceSheetAbstract" xlink:to="lab_hmh_UnauditedProFormaConsolidatedBalanceSheetAbstract" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_UnauditedProFormaConsolidatedBalanceSheetTable" xlink:label="loc_hmh_UnauditedProFormaConsolidatedBalanceSheetTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_UnauditedProFormaConsolidatedBalanceSheetTable" xml:lang="en-US">Unaudited Pro Forma Consolidated Balance Sheet [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_UnauditedProFormaConsolidatedBalanceSheetTable" xlink:to="lab_hmh_UnauditedProFormaConsolidatedBalanceSheetTable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_UnauditedProFormaConsolidatedBalanceSheetLineItems" xlink:label="loc_hmh_UnauditedProFormaConsolidatedBalanceSheetLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_UnauditedProFormaConsolidatedBalanceSheetLineItems" xml:lang="en-US">Unaudited Pro Forma Consolidated Balance Sheet [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_UnauditedProFormaConsolidatedBalanceSheetLineItems" xlink:to="lab_hmh_UnauditedProFormaConsolidatedBalanceSheetLineItems" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_NotesToUnauditedProFormaConsolidatedBalanceSheetTextBlock" xlink:label="loc_hmh_NotesToUnauditedProFormaConsolidatedBalanceSheetTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_NotesToUnauditedProFormaConsolidatedBalanceSheetTextBlock" xml:lang="en-US">Notes to unaudited pro forma consolidated balance sheet</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_NotesToUnauditedProFormaConsolidatedBalanceSheetTextBlock" xlink:to="lab_hmh_NotesToUnauditedProFormaConsolidatedBalanceSheetTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_NotesToUnauditedProFormaConsolidatedBalanceSheetTextBlock" xml:lang="en-US">Notes to unaudited pro forma consolidated balance sheet.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_UnauditedProFormaConsolidatedStatementOfIncomeAbstract" xlink:label="loc_hmh_UnauditedProFormaConsolidatedStatementOfIncomeAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_UnauditedProFormaConsolidatedStatementOfIncomeAbstract" xml:lang="en-US">Unaudited Pro Forma Consolidated Statement Of Income [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_UnauditedProFormaConsolidatedStatementOfIncomeAbstract" xlink:to="lab_hmh_UnauditedProFormaConsolidatedStatementOfIncomeAbstract" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_UnauditedProFormaConsolidatedStatementOfIncomeTable" xlink:label="loc_hmh_UnauditedProFormaConsolidatedStatementOfIncomeTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_UnauditedProFormaConsolidatedStatementOfIncomeTable" xml:lang="en-US">Unaudited Pro Forma Consolidated Statement Of Income [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_UnauditedProFormaConsolidatedStatementOfIncomeTable" xlink:to="lab_hmh_UnauditedProFormaConsolidatedStatementOfIncomeTable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_UnauditedProFormaConsolidatedStatementOfIncomeLineItems" xlink:label="loc_hmh_UnauditedProFormaConsolidatedStatementOfIncomeLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_UnauditedProFormaConsolidatedStatementOfIncomeLineItems" xml:lang="en-US">Unaudited Pro Forma Consolidated Statement Of Income [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_UnauditedProFormaConsolidatedStatementOfIncomeLineItems" xlink:to="lab_hmh_UnauditedProFormaConsolidatedStatementOfIncomeLineItems" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_UnauditedProFormaConsolidatedStatementOfIncomeTextBlock" xlink:label="loc_hmh_UnauditedProFormaConsolidatedStatementOfIncomeTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_UnauditedProFormaConsolidatedStatementOfIncomeTextBlock" xml:lang="en-US">Unaudited Pro Forma Consolidated Statement Of Income [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_UnauditedProFormaConsolidatedStatementOfIncomeTextBlock" xml:lang="en-US">Notes to unaudited pro forma consolidated statement of income</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_UnauditedProFormaConsolidatedStatementOfIncomeTextBlock" xlink:to="lab_hmh_UnauditedProFormaConsolidatedStatementOfIncomeTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_UnauditedProFormaConsolidatedStatementOfIncomeTextBlock" xml:lang="en-US">Notes to unaudited pro forma consolidated statement of income.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventsAbstract" xlink:label="loc_us-gaap_SubsequentEventsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SubsequentEventsAbstract" xml:lang="en-US">Subsequent Events [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventsAbstract" xlink:to="lab_us-gaap_SubsequentEventsAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventTable" xlink:label="loc_us-gaap_SubsequentEventTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SubsequentEventTable" xml:lang="en-US">Subsequent Event [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventTable" xlink:to="lab_us-gaap_SubsequentEventTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventLineItems" xlink:label="loc_us-gaap_SubsequentEventLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SubsequentEventLineItems" xml:lang="en-US">Subsequent Event [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventLineItems" xlink:to="lab_us-gaap_SubsequentEventLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsequentEventsTextBlock" xlink:label="loc_us-gaap_SubsequentEventsTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SubsequentEventsTextBlock" xml:lang="en-US">Subsequent Events [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SubsequentEventsTextBlock" xml:lang="en-US">Subsequent events</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventsTextBlock" xlink:to="lab_us-gaap_SubsequentEventsTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryDisclosureAbstract" xlink:label="loc_us-gaap_InventoryDisclosureAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InventoryDisclosureAbstract" xml:lang="en-US">Inventory Disclosure [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryDisclosureAbstract" xlink:to="lab_us-gaap_InventoryDisclosureAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryCurrentTable" xlink:label="loc_us-gaap_InventoryCurrentTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InventoryCurrentTable" xml:lang="en-US">Inventory, Current [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryCurrentTable" xlink:to="lab_us-gaap_InventoryCurrentTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryLineItems" xlink:label="loc_us-gaap_InventoryLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InventoryLineItems" xml:lang="en-US">Inventory [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryLineItems" xlink:to="lab_us-gaap_InventoryLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryDisclosureTextBlock" xlink:label="loc_us-gaap_InventoryDisclosureTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InventoryDisclosureTextBlock" xml:lang="en-US">Inventory Disclosure [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_InventoryDisclosureTextBlock" xml:lang="en-US">Inventories</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryDisclosureTextBlock" xlink:to="lab_us-gaap_InventoryDisclosureTextBlock" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_GoodwillAbstract" xlink:label="loc_hmh_GoodwillAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_GoodwillAbstract" xml:lang="en-US">Goodwill [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_GoodwillAbstract" xlink:to="lab_hmh_GoodwillAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfGoodwillTable" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfGoodwillTable" xml:lang="en-US">Goodwill [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable" xlink:to="lab_us-gaap_ScheduleOfGoodwillTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GoodwillLineItems" xlink:label="loc_us-gaap_GoodwillLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GoodwillLineItems" xml:lang="en-US">Goodwill [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillLineItems" xlink:to="lab_us-gaap_GoodwillLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GoodwillDisclosureTextBlock" xlink:label="loc_us-gaap_GoodwillDisclosureTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GoodwillDisclosureTextBlock" xml:lang="en-US">Goodwill [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_GoodwillDisclosureTextBlock" xml:lang="en-US">Goodwill</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillDisclosureTextBlock" xlink:to="lab_us-gaap_GoodwillDisclosureTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentAbstract" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentAbstract" xml:lang="en-US">Property, Plant, and Equipment [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentAbstract" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xml:lang="en-US">Property, Plant, and Equipment [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" xlink:to="lab_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentLineItems" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentLineItems" xml:lang="en-US">Property, Plant, and Equipment [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" xml:lang="en-US">Property, Plant, and Equipment [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" xml:lang="en-US">Property, plant and equipment</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentDisclosureTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" xml:lang="en-US">Derivative Instruments and Hedging Activities Disclosure [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" xlink:to="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosureAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xml:lang="en-US">Fair Value, Recurring and Nonrecurring [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" xlink:to="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xlink:label="loc_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueAssetsAndLiabilitiesMeasuredOnRecurringAndNonrecurringBasisLineItems" xml:lang="en-US">Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]</link:label>
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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativesAndFairValueTextBlock" xlink:label="loc_us-gaap_DerivativesAndFairValueTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativesAndFairValueTextBlock" xml:lang="en-US">Derivatives and Fair Value [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DerivativesAndFairValueTextBlock" xml:lang="en-US">Financial Instruments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativesAndFairValueTextBlock" xlink:to="lab_us-gaap_DerivativesAndFairValueTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilitiesDisclosureAbstract" xlink:label="loc_us-gaap_OtherLiabilitiesDisclosureAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherLiabilitiesDisclosureAbstract" xml:lang="en-US">Other Liabilities Disclosure [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherLiabilitiesDisclosureAbstract" xlink:to="lab_us-gaap_OtherLiabilitiesDisclosureAbstract" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OtherCurrentLiabilitiesTable" xlink:label="loc_hmh_OtherCurrentLiabilitiesTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OtherCurrentLiabilitiesTable" xml:lang="en-US">Other Current Liabilities [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OtherCurrentLiabilitiesTable" xlink:to="lab_hmh_OtherCurrentLiabilitiesTable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OtherCurrentLiabilitiesLineItems" xlink:label="loc_hmh_OtherCurrentLiabilitiesLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OtherCurrentLiabilitiesLineItems" xml:lang="en-US">Other Current Liabilities [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OtherCurrentLiabilitiesLineItems" xlink:to="lab_hmh_OtherCurrentLiabilitiesLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilitiesDisclosureTextBlock" xlink:label="loc_us-gaap_OtherLiabilitiesDisclosureTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherLiabilitiesDisclosureTextBlock" xml:lang="en-US">Other Liabilities Disclosure [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherLiabilitiesDisclosureTextBlock" xml:lang="en-US">Other Current Liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherLiabilitiesDisclosureTextBlock" xlink:to="lab_us-gaap_OtherLiabilitiesDisclosureTextBlock" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_IntangibleAssetsAbstract" xlink:label="loc_hmh_IntangibleAssetsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_IntangibleAssetsAbstract" xml:lang="en-US">Intangible assets [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_IntangibleAssetsAbstract" xlink:to="lab_hmh_IntangibleAssetsAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xml:lang="en-US">Intangible Asset, Finite-Lived [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" xlink:to="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems" xml:lang="en-US">Intangible Asset, Finite-Lived [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntangibleAssetsDisclosureTextBlock" xlink:label="loc_us-gaap_IntangibleAssetsDisclosureTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IntangibleAssetsDisclosureTextBlock" xml:lang="en-US">Intangible Asset [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_IntangibleAssetsDisclosureTextBlock" xml:lang="en-US">Intangible assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IntangibleAssetsDisclosureTextBlock" xlink:to="lab_us-gaap_IntangibleAssetsDisclosureTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LeasesAbstract" xlink:label="loc_us-gaap_LeasesAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LeasesAbstract" xml:lang="en-US">Leases [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LeasesAbstract" xlink:to="lab_us-gaap_LeasesAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeLeaseDescriptionTable" xlink:label="loc_us-gaap_LesseeLeaseDescriptionTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LesseeLeaseDescriptionTable" xml:lang="en-US">Lessee, Lease, Description [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeLeaseDescriptionTable" xlink:to="lab_us-gaap_LesseeLeaseDescriptionTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeLeaseDescriptionLineItems" xlink:label="loc_us-gaap_LesseeLeaseDescriptionLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LesseeLeaseDescriptionLineItems" xml:lang="en-US">Lessee, Lease, Description [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeLeaseDescriptionLineItems" xlink:to="lab_us-gaap_LesseeLeaseDescriptionLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeasesTextBlock" xlink:label="loc_us-gaap_LesseeOperatingLeasesTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LesseeOperatingLeasesTextBlock" xml:lang="en-US">Lessee, Operating Leases [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LesseeOperatingLeasesTextBlock" xml:lang="en-US">Leases</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeOperatingLeasesTextBlock" xlink:to="lab_us-gaap_LesseeOperatingLeasesTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtDisclosureAbstract" xlink:label="loc_us-gaap_DebtDisclosureAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtDisclosureAbstract" xml:lang="en-US">Debt Disclosure [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtDisclosureAbstract" xlink:to="lab_us-gaap_DebtDisclosureAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentTable" xlink:label="loc_us-gaap_DebtInstrumentTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtInstrumentTable" xml:lang="en-US">Schedule of Long-Term Debt Instruments [Table]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DebtInstrumentTable" xml:lang="en-US">Schedule of Long-Term Debt Instruments [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentTable" xlink:to="lab_us-gaap_DebtInstrumentTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentLineItems" xlink:label="loc_us-gaap_DebtInstrumentLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtInstrumentLineItems" xml:lang="en-US">Debt Instrument [Line Items]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DebtInstrumentLineItems" xml:lang="en-US">Debt Instrument [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentLineItems" xlink:to="lab_us-gaap_DebtInstrumentLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtDisclosureTextBlock" xlink:label="loc_us-gaap_DebtDisclosureTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtDisclosureTextBlock" xml:lang="en-US">Debt Disclosure [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DebtDisclosureTextBlock" xml:lang="en-US">Debt</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtDisclosureTextBlock" xlink:to="lab_us-gaap_DebtDisclosureTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueTable" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DisaggregationOfRevenueTable" xml:lang="en-US">Disaggregation of Revenue [Table]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DisaggregationOfRevenueTable" xml:lang="en-US">Disaggregation of Revenue [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable" xlink:to="lab_us-gaap_DisaggregationOfRevenueTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueLineItems" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DisaggregationOfRevenueLineItems" xml:lang="en-US">Disaggregation of Revenue [Line Items]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DisaggregationOfRevenueLineItems" xml:lang="en-US">Disaggregation of Revenue [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems" xlink:to="lab_us-gaap_DisaggregationOfRevenueLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerTextBlock" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerTextBlock" xml:lang="en-US">Revenue from Contract with Customer [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerTextBlock" xml:lang="en-US">Revenue from Contracts with Customers</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueFromContractWithCustomerTextBlock" xlink:to="lab_us-gaap_RevenueFromContractWithCustomerTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PayablesAndAccrualsAbstract" xlink:label="loc_us-gaap_PayablesAndAccrualsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PayablesAndAccrualsAbstract" xml:lang="en-US">Payables and Accruals [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PayablesAndAccrualsAbstract" xlink:to="lab_us-gaap_PayablesAndAccrualsAbstract" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AccruedExpensesTable" xlink:label="loc_hmh_AccruedExpensesTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AccruedExpensesTable" xml:lang="en-US">Accrued expenses [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AccruedExpensesTable" xlink:to="lab_hmh_AccruedExpensesTable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AccruedExpensesLineItems" xlink:label="loc_hmh_AccruedExpensesLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AccruedExpensesLineItems" xml:lang="en-US">Accrued expenses [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AccruedExpensesLineItems" xlink:to="lab_hmh_AccruedExpensesLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentTextBlock" xlink:label="loc_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentTextBlock" xml:lang="en-US">Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentTextBlock" xml:lang="en-US">Accrued Expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentTextBlock" xlink:to="lab_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureCurrentTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureNoncurrentTextBlock" xlink:label="loc_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureNoncurrentTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureNoncurrentTextBlock" xml:lang="en-US">Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Noncurrent [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureNoncurrentTextBlock" xml:lang="en-US">Other Liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureNoncurrentTextBlock" xlink:to="lab_us-gaap_AccountsPayableAccruedLiabilitiesAndOtherLiabilitiesDisclosureNoncurrentTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EquityAbstract" xlink:label="loc_us-gaap_EquityAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EquityAbstract" xml:lang="en-US">Equity [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquityAbstract" xlink:to="lab_us-gaap_EquityAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:label="loc_us-gaap_StockholdersEquityNoteDisclosureTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock" xml:lang="en-US">Equity [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock" xml:lang="en-US">Equity</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:to="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:label="loc_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xml:lang="en-US">Share-Based Payment Arrangement [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" xlink:to="lab_us-gaap_DisclosureOfCompensationRelatedCostsSharebasedPaymentsAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:label="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xml:lang="en-US">Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" xlink:to="lab_us-gaap_ScheduleOfEmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xlink:label="loc_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xml:lang="en-US">Share-Based Payment Arrangement [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xml:lang="en-US">Share-based Compensation</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" xlink:to="lab_us-gaap_DisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CompensationAndRetirementDisclosureAbstract" xlink:label="loc_us-gaap_CompensationAndRetirementDisclosureAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CompensationAndRetirementDisclosureAbstract" xml:lang="en-US">Retirement Benefits [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CompensationAndRetirementDisclosureAbstract" xlink:to="lab_us-gaap_CompensationAndRetirementDisclosureAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:label="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xml:lang="en-US">Defined Benefit Plan [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" xlink:to="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanTextBlock" xlink:label="loc_us-gaap_DefinedBenefitPlanTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanTextBlock" xml:lang="en-US">Defined Benefit Plan [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanTextBlock" xml:lang="en-US">Employee Benefit Expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanTextBlock" xlink:to="lab_us-gaap_DefinedBenefitPlanTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxDisclosureAbstract" xlink:label="loc_us-gaap_IncomeTaxDisclosureAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeTaxDisclosureAbstract" xml:lang="en-US">Income Tax Disclosure [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxDisclosureAbstract" xlink:to="lab_us-gaap_IncomeTaxDisclosureAbstract" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_IncomeTaxesTable" xlink:label="loc_hmh_IncomeTaxesTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_IncomeTaxesTable" xml:lang="en-US">Income taxes [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_IncomeTaxesTable" xlink:to="lab_hmh_IncomeTaxesTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_IncomeTaxesTable" xml:lang="en-US">Income taxes.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_IncomeTaxesLineItems" xlink:label="loc_hmh_IncomeTaxesLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_IncomeTaxesLineItems" xml:lang="en-US">Income taxes [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_IncomeTaxesLineItems" xlink:to="lab_hmh_IncomeTaxesLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxDisclosureTextBlock" xlink:label="loc_us-gaap_IncomeTaxDisclosureTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeTaxDisclosureTextBlock" xml:lang="en-US">Income Tax Disclosure [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncomeTaxDisclosureTextBlock" xml:lang="en-US">Income Taxes</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxDisclosureTextBlock" xlink:to="lab_us-gaap_IncomeTaxDisclosureTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xml:lang="en-US">Commitments and Contingencies Disclosure [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:to="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable" xml:lang="en-US">Restructuring Cost [Table]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable" xml:lang="en-US">Restructuring Cost [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable" xlink:to="lab_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringCostAndReserveLineItems" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RestructuringCostAndReserveLineItems" xml:lang="en-US">Restructuring Cost and Reserve [Line Items]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RestructuringCostAndReserveLineItems" xml:lang="en-US">Restructuring Cost and Reserve [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems" xlink:to="lab_us-gaap_RestructuringCostAndReserveLineItems" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_CommitmentsContingenciesRestructuringAndGuaranteesTextBlock" xlink:label="loc_hmh_CommitmentsContingenciesRestructuringAndGuaranteesTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_CommitmentsContingenciesRestructuringAndGuaranteesTextBlock" xml:lang="en-US">Commitments, Contingencies, Restructuring And Guarantees [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_CommitmentsContingenciesRestructuringAndGuaranteesTextBlock" xml:lang="en-US">Commitments and contingencies</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_CommitmentsContingenciesRestructuringAndGuaranteesTextBlock" xlink:to="lab_hmh_CommitmentsContingenciesRestructuringAndGuaranteesTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_CommitmentsContingenciesRestructuringAndGuaranteesTextBlock" xml:lang="en-US">Commitments, Contingencies, Restructuring And Guarantees</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsAbstract" xlink:label="loc_us-gaap_RelatedPartyTransactionsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RelatedPartyTransactionsAbstract" xml:lang="en-US">Related Party Transactions [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionsAbstract" xlink:to="lab_us-gaap_RelatedPartyTransactionsAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xml:lang="en-US">Related Party Transaction [Table]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xml:lang="en-US">Related Party Transaction [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:to="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionLineItems" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RelatedPartyTransactionLineItems" xml:lang="en-US">Related Party Transaction [Line Items]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RelatedPartyTransactionLineItems" xml:lang="en-US">Related Party Transaction [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems" xlink:to="lab_us-gaap_RelatedPartyTransactionLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:label="loc_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xml:lang="en-US">Related Party Transactions Disclosure [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xml:lang="en-US">Related Party Transactions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:to="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingAbstract" xlink:label="loc_us-gaap_SegmentReportingAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SegmentReportingAbstract" xml:lang="en-US">Segment Reporting [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingAbstract" xlink:to="lab_us-gaap_SegmentReportingAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xml:lang="en-US">Segment Reporting [Table]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xml:lang="en-US">Segment Reporting [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:to="lab_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SegmentReportingInformationLineItems" xml:lang="en-US">Segment Reporting [Line Items]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SegmentReportingInformationLineItems" xml:lang="en-US">Segment Reporting [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems" xlink:to="lab_us-gaap_SegmentReportingInformationLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingDisclosureTextBlock" xlink:label="loc_us-gaap_SegmentReportingDisclosureTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SegmentReportingDisclosureTextBlock" xml:lang="en-US">Segment Reporting [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SegmentReportingDisclosureTextBlock" xml:lang="en-US">Segment Information</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingDisclosureTextBlock" xlink:to="lab_us-gaap_SegmentReportingDisclosureTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EarningsPerShareAbstract" xml:lang="en-US">Earnings Per Share [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareAbstract" xlink:to="lab_us-gaap_EarningsPerShareAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEarningsPerShareBasicByCommonClassTable" xlink:label="loc_us-gaap_ScheduleOfEarningsPerShareBasicByCommonClassTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareBasicByCommonClassTable" xml:lang="en-US">Earnings Per Share, Basic, by Common Class, Including Two-Class Method [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEarningsPerShareBasicByCommonClassTable" xlink:to="lab_us-gaap_ScheduleOfEarningsPerShareBasicByCommonClassTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareBasicLineItems" xlink:label="loc_us-gaap_EarningsPerShareBasicLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EarningsPerShareBasicLineItems" xml:lang="en-US">Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareBasicLineItems" xlink:to="lab_us-gaap_EarningsPerShareBasicLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EarningsPerShareTextBlock" xlink:label="loc_us-gaap_EarningsPerShareTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EarningsPerShareTextBlock" xml:lang="en-US">Earnings Per Share [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_EarningsPerShareTextBlock" xml:lang="en-US">Earnings per Share</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareTextBlock" xlink:to="lab_us-gaap_EarningsPerShareTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:label="loc_us-gaap_BasisOfAccountingPolicyPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xml:lang="en-US">Basis of Accounting, Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xml:lang="en-US">Basis of Presentation</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:to="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PriorPeriodReclassificationAdjustmentDescription" xlink:label="loc_us-gaap_PriorPeriodReclassificationAdjustmentDescription" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PriorPeriodReclassificationAdjustmentDescription" xml:lang="en-US">Reclassification, Comparability Adjustment [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PriorPeriodReclassificationAdjustmentDescription" xml:lang="en-US">Reclassification</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PriorPeriodReclassificationAdjustmentDescription" xlink:to="lab_us-gaap_PriorPeriodReclassificationAdjustmentDescription" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy" xlink:label="loc_us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy" xml:lang="en-US">Share-Based Payment Arrangement [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy" xml:lang="en-US">Share-based Compensation</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy" xlink:to="lab_us-gaap_ShareBasedCompensationOptionAndIncentivePlansPolicy" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:label="loc_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xml:lang="en-US">New Accounting Pronouncements, Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xml:lang="en-US">New Accounting Standards to be Adopted</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:to="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DescriptionOfBusinessPolicyTextBlock" xlink:label="loc_hmh_DescriptionOfBusinessPolicyTextBlock" />
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_DescriptionOfBusinessPolicyTextBlock" xml:lang="en-US">Description of business</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DescriptionOfBusinessPolicyTextBlock" xlink:to="lab_hmh_DescriptionOfBusinessPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DescriptionOfBusinessPolicyTextBlock" xml:lang="en-US">Description of business policy text block.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UseOfEstimates" xlink:label="loc_us-gaap_UseOfEstimates" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_UseOfEstimates" xml:lang="en-US">Use of Estimates, Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_UseOfEstimates" xml:lang="en-US">Use of Estimates</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UseOfEstimates" xlink:to="lab_us-gaap_UseOfEstimates" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock" xlink:label="loc_us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock" xml:lang="en-US">Foreign Currency Transactions and Translations Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock" xml:lang="en-US">Foreign currency</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock" xlink:to="lab_us-gaap_ForeignCurrencyTransactionsAndTranslationsPolicyTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationsPolicy" xlink:label="loc_us-gaap_BusinessCombinationsPolicy" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationsPolicy" xml:lang="en-US">Business Combination [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationsPolicy" xml:lang="en-US">Business combinations</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationsPolicy" xlink:to="lab_us-gaap_BusinessCombinationsPolicy" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OfferingCostsPolicyTextBlock" xlink:label="loc_hmh_OfferingCostsPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OfferingCostsPolicyTextBlock" xml:lang="en-US">Offering Costs [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_OfferingCostsPolicyTextBlock" xml:lang="en-US">Offering costs</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OfferingCostsPolicyTextBlock" xlink:to="lab_hmh_OfferingCostsPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_OfferingCostsPolicyTextBlock" xml:lang="en-US">Offering costs policy text block.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:label="loc_us-gaap_CashAndCashEquivalentsPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock" xml:lang="en-US">Cash and Cash Equivalents, Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock" xml:lang="en-US">Cash and cash equivalents</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:to="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReceivablesPolicyTextBlock" xlink:label="loc_us-gaap_ReceivablesPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ReceivablesPolicyTextBlock" xml:lang="en-US">Receivable [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ReceivablesPolicyTextBlock" xml:lang="en-US">Accounts receivable</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReceivablesPolicyTextBlock" xlink:to="lab_us-gaap_ReceivablesPolicyTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueOfFinancialInstrumentsPolicy" xlink:label="loc_us-gaap_FairValueOfFinancialInstrumentsPolicy" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueOfFinancialInstrumentsPolicy" xml:lang="en-US">Fair Value of Financial Instruments, Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FairValueOfFinancialInstrumentsPolicy" xml:lang="en-US">Derivative financial instruments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueOfFinancialInstrumentsPolicy" xlink:to="lab_us-gaap_FairValueOfFinancialInstrumentsPolicy" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ShareCapitalPolicyTextBlock" xlink:label="loc_hmh_ShareCapitalPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ShareCapitalPolicyTextBlock" xml:lang="en-US">Share Capital [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ShareCapitalPolicyTextBlock" xml:lang="en-US">Share capital</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ShareCapitalPolicyTextBlock" xlink:to="lab_hmh_ShareCapitalPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ShareCapitalPolicyTextBlock" xml:lang="en-US">Share capital policy text block.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryPolicyTextBlock" xlink:label="loc_us-gaap_InventoryPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InventoryPolicyTextBlock" xml:lang="en-US">Inventory, Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_InventoryPolicyTextBlock" xml:lang="en-US">Inventories</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryPolicyTextBlock" xlink:to="lab_us-gaap_InventoryPolicyTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskCreditRisk" xlink:label="loc_us-gaap_ConcentrationRiskCreditRisk" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ConcentrationRiskCreditRisk" xml:lang="en-US">Concentration Risk, Credit Risk, Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ConcentrationRiskCreditRisk" xml:lang="en-US">Concentration risk</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskCreditRisk" xlink:to="lab_us-gaap_ConcentrationRiskCreditRisk" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeLeasesPolicyTextBlock" xlink:label="loc_us-gaap_LesseeLeasesPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LesseeLeasesPolicyTextBlock" xml:lang="en-US">Lessee, Leases [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LesseeLeasesPolicyTextBlock" xml:lang="en-US">Leases</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeLeasesPolicyTextBlock" xlink:to="lab_us-gaap_LesseeLeasesPolicyTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentImpairment" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentImpairment" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentImpairment" xml:lang="en-US">Property, Plant and Equipment, Impairment [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentImpairment" xml:lang="en-US">Property, plant and equipment</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentImpairment" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentImpairment" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GoodwillAndIntangibleAssetsGoodwillPolicy" xlink:label="loc_us-gaap_GoodwillAndIntangibleAssetsGoodwillPolicy" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsGoodwillPolicy" xml:lang="en-US">Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsGoodwillPolicy" xml:lang="en-US">Goodwill</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillAndIntangibleAssetsGoodwillPolicy" xlink:to="lab_us-gaap_GoodwillAndIntangibleAssetsGoodwillPolicy" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GoodwillAndIntangibleAssetsIntangibleAssetsPolicy" xlink:label="loc_us-gaap_GoodwillAndIntangibleAssetsIntangibleAssetsPolicy" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsIntangibleAssetsPolicy" xml:lang="en-US">Goodwill and Intangible Assets, Intangible Assets, Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_GoodwillAndIntangibleAssetsIntangibleAssetsPolicy" xml:lang="en-US">Other intangible assets, patents and rights and customer relations</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillAndIntangibleAssetsIntangibleAssetsPolicy" xlink:to="lab_us-gaap_GoodwillAndIntangibleAssetsIntangibleAssetsPolicy" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerPolicyTextBlock" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerPolicyTextBlock" xml:lang="en-US">Revenue from Contract with Customer [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerPolicyTextBlock" xml:lang="en-US">Revenue from contracts with customers</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueFromContractWithCustomerPolicyTextBlock" xlink:to="lab_us-gaap_RevenueFromContractWithCustomerPolicyTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxPolicyTextBlock" xlink:label="loc_us-gaap_IncomeTaxPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeTaxPolicyTextBlock" xml:lang="en-US">Income Tax, Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncomeTaxPolicyTextBlock" xml:lang="en-US">Income taxes</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxPolicyTextBlock" xlink:to="lab_us-gaap_IncomeTaxPolicyTextBlock" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AccruedLiabilitiesPolicyTextBlock" xlink:label="loc_hmh_AccruedLiabilitiesPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AccruedLiabilitiesPolicyTextBlock" xml:lang="en-US">Accrued Liabilities [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_AccruedLiabilitiesPolicyTextBlock" xml:lang="en-US">Accrued liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AccruedLiabilitiesPolicyTextBlock" xlink:to="lab_hmh_AccruedLiabilitiesPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AccruedLiabilitiesPolicyTextBlock" xml:lang="en-US">Accrued Liabilities policy text block.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeStockOwnershipPlanESOPPolicy" xlink:label="loc_us-gaap_EmployeeStockOwnershipPlanESOPPolicy" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EmployeeStockOwnershipPlanESOPPolicy" xml:lang="en-US">Employee Stock Ownership Plan (ESOP), Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_EmployeeStockOwnershipPlanESOPPolicy" xml:lang="en-US">Employee benefits</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeStockOwnershipPlanESOPPolicy" xlink:to="lab_us-gaap_EmployeeStockOwnershipPlanESOPPolicy" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementPolicyPolicyTextBlock" xlink:label="loc_us-gaap_FairValueMeasurementPolicyPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueMeasurementPolicyPolicyTextBlock" xml:lang="en-US">Fair Value Measurement, Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FairValueMeasurementPolicyPolicyTextBlock" xml:lang="en-US">Fair value measurement</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueMeasurementPolicyPolicyTextBlock" xlink:to="lab_us-gaap_FairValueMeasurementPolicyPolicyTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativesMethodsOfAccountingHedgingDerivatives" xlink:label="loc_us-gaap_DerivativesMethodsOfAccountingHedgingDerivatives" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativesMethodsOfAccountingHedgingDerivatives" xml:lang="en-US">Derivatives, Methods of Accounting, Hedging Derivatives [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DerivativesMethodsOfAccountingHedgingDerivatives" xml:lang="en-US">Hedging activities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativesMethodsOfAccountingHedgingDerivatives" xlink:to="lab_us-gaap_DerivativesMethodsOfAccountingHedgingDerivatives" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InvestmentPolicyTextBlock" xlink:label="loc_us-gaap_InvestmentPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InvestmentPolicyTextBlock" xml:lang="en-US">Investment, Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_InvestmentPolicyTextBlock" xml:lang="en-US">Investment in subsidiaries</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentPolicyTextBlock" xlink:to="lab_us-gaap_InvestmentPolicyTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredChargesPolicyTextBlock" xlink:label="loc_us-gaap_DeferredChargesPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredChargesPolicyTextBlock" xml:lang="en-US">Deferred Charges, Policy [Policy Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredChargesPolicyTextBlock" xml:lang="en-US">Offering Costs</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredChargesPolicyTextBlock" xlink:to="lab_us-gaap_DeferredChargesPolicyTextBlock" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OrganizationCostsPolicyTextBlock" xlink:label="loc_hmh_OrganizationCostsPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OrganizationCostsPolicyTextBlock" xml:lang="en-US">Organization Costs Policy [Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_OrganizationCostsPolicyTextBlock" xml:lang="en-US">Organization costs</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OrganizationCostsPolicyTextBlock" xlink:to="lab_hmh_OrganizationCostsPolicyTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_OrganizationCostsPolicyTextBlock" xml:lang="en-US">Organization costs policy.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTableTextBlock" xlink:label="loc_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTableTextBlock" xml:lang="en-US">Schedule of Property Plant And Equipment Useful Life [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTableTextBlock" xml:lang="en-US">Schedule of Property Plant And Equipment Useful Life</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTableTextBlock" xlink:to="lab_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTableTextBlock" xml:lang="en-US">Schedule of property plant and equipment useful life table text block.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xml:lang="en-US">Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xml:lang="en-US">Schedule of Earnings Per Share, Basic and Diluted</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xml:lang="en-US">Schedule of Earnings Per Share</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTextBlock" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTextBlock" xml:lang="en-US">Business Combination [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTextBlock" xml:lang="en-US">Summary of the Fair Value of Assets Acquired and Liabilities Assumed</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTextBlock" xml:lang="en-US">Summary of Net Impact of Drillform Acquisition on the Income Statement</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTextBlock" xlink:to="lab_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock" xml:lang="en-US">Business Combination, Recognized Asset Acquired and Liability Assumed [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock" xml:lang="en-US">Schedule of Recognized Identified Assets Acquired and Liabilities Assumed</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTextBlock" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTextBlock" xml:lang="en-US">Business Combination, Intangible Asset, Acquired, Finite-Lived [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTextBlock" xml:lang="en-US">Schedule of the Fair Value of Acquired Identifiable Intangible Assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTextBlock" xlink:to="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsAcquiredAsPartOfBusinessCombinationTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionProFormaInformationTextBlock" xlink:label="loc_us-gaap_BusinessAcquisitionProFormaInformationTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionProFormaInformationTextBlock" xml:lang="en-US">Business Combination, Pro Forma Information [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessAcquisitionProFormaInformationTextBlock" xml:lang="en-US">Summary of Supplement of the Company on an Pro Forma Information</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionProFormaInformationTextBlock" xlink:to="lab_us-gaap_BusinessAcquisitionProFormaInformationTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfInventoryCurrentTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfInventoryCurrentTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfInventoryCurrentTableTextBlock" xml:lang="en-US">Schedule of Inventory, Current [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfInventoryCurrentTableTextBlock" xml:lang="en-US">Schedule Of Inventories, Net Of Reserves</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfInventoryCurrentTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfInventoryCurrentTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfGoodwillTextBlock" xlink:label="loc_us-gaap_ScheduleOfGoodwillTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfGoodwillTextBlock" xml:lang="en-US">Goodwill [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ScheduleOfGoodwillTextBlock" xml:lang="en-US">Schedule Of Changes In Carrying Value Of Goodwill</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfGoodwillTextBlock" xlink:to="lab_us-gaap_ScheduleOfGoodwillTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTextBlock" xml:lang="en-US">Property, Plant, and Equipment [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTextBlock" xml:lang="en-US">Schedule Of Property, Plant And Equipment</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTextBlock" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock" xml:lang="en-US">Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock" xml:lang="en-US">Schedule Of Financial Instruments That Are Measured At Fair Value On A Recurring Basis</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfFairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfDerivativeInstrumentsTextBlock" xlink:label="loc_us-gaap_ScheduleOfDerivativeInstrumentsTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfDerivativeInstrumentsTextBlock" xml:lang="en-US">Schedule of Derivative Instruments [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfDerivativeInstrumentsTextBlock" xml:lang="en-US">Schedule Of Fair Value Of The Derivative Financial Instruments And A Maturity Analysis Of The Derivatives Cash Flows</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDerivativeInstrumentsTextBlock" xlink:to="lab_us-gaap_ScheduleOfDerivativeInstrumentsTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfDerivativeInstrumentsEffectOnOtherComprehensiveIncomeLossTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfDerivativeInstrumentsEffectOnOtherComprehensiveIncomeLossTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfDerivativeInstrumentsEffectOnOtherComprehensiveIncomeLossTableTextBlock" xml:lang="en-US">Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss) [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ScheduleOfDerivativeInstrumentsEffectOnOtherComprehensiveIncomeLossTableTextBlock" xml:lang="en-US">Schedule Of Reconciliation By Risk Category Of Components Of Equity And Analysis Of OCI Items, Net Of Tax</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDerivativeInstrumentsEffectOnOtherComprehensiveIncomeLossTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfDerivativeInstrumentsEffectOnOtherComprehensiveIncomeLossTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AcceleratedShareRepurchasesTable" xlink:label="loc_us-gaap_AcceleratedShareRepurchasesTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AcceleratedShareRepurchasesTable" xml:lang="en-US">Accelerated Share Repurchases [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AcceleratedShareRepurchasesTable" xlink:to="lab_us-gaap_AcceleratedShareRepurchasesTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AcceleratedShareRepurchasesLineItems" xlink:label="loc_us-gaap_AcceleratedShareRepurchasesLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AcceleratedShareRepurchasesLineItems" xml:lang="en-US">Accelerated Share Repurchases [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AcceleratedShareRepurchasesLineItems" xlink:to="lab_us-gaap_AcceleratedShareRepurchasesLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherCurrentLiabilitiesTableTextBlock" xlink:label="loc_us-gaap_OtherCurrentLiabilitiesTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherCurrentLiabilitiesTableTextBlock" xml:lang="en-US">Other Current Liabilities [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherCurrentLiabilitiesTableTextBlock" xml:lang="en-US">Schedule of Other Current Liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherCurrentLiabilitiesTableTextBlock" xlink:to="lab_us-gaap_OtherCurrentLiabilitiesTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock" xml:lang="en-US">Intangible Asset, Finite-Lived [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock" xml:lang="en-US">Schedule Of Intangible Assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseTableTextBlock" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseTableTextBlock" xml:lang="en-US">Intangible Asset, Finite-Lived, Amortization Expense [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseTableTextBlock" xml:lang="en-US">Schedule Of The Estimated Future Amortization Expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseTableTextBlock" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AssetsAndLiabilitiesLesseeTableTextBlock" xlink:label="loc_hmh_AssetsAndLiabilitiesLesseeTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AssetsAndLiabilitiesLesseeTableTextBlock" xml:lang="en-US">Assets And Liabilities, Lessee [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_AssetsAndLiabilitiesLesseeTableTextBlock" xml:lang="en-US">Schedule of Supplemental Consolidated Balance Sheet Information Related to Leases</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AssetsAndLiabilitiesLesseeTableTextBlock" xlink:to="lab_hmh_AssetsAndLiabilitiesLesseeTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AssetsAndLiabilitiesLesseeTableTextBlock" xml:lang="en-US">Assets And Liabilities, Lessee</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LeaseCostTableTextBlock" xlink:label="loc_us-gaap_LeaseCostTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LeaseCostTableTextBlock" xml:lang="en-US">Lease, Cost [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LeaseCostTableTextBlock" xml:lang="en-US">Schedule of the components of lease expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LeaseCostTableTextBlock" xlink:to="lab_us-gaap_LeaseCostTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock" xml:lang="en-US">Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock" xml:lang="en-US">Schedule of Lessee, Operating Lease, Liability, to be Paid, Maturity</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock" xlink:to="lab_us-gaap_LesseeOperatingLeaseLiabilityMaturityTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfWeightedAverageRemainingTermAndWeightedAverageDiscountRatesTableTextBlock" xlink:label="loc_hmh_ScheduleOfWeightedAverageRemainingTermAndWeightedAverageDiscountRatesTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfWeightedAverageRemainingTermAndWeightedAverageDiscountRatesTableTextBlock" xml:lang="en-US">Schedule of Weighted Average Remaining Term and Weighted Average Discount Rates [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ScheduleOfWeightedAverageRemainingTermAndWeightedAverageDiscountRatesTableTextBlock" xml:lang="en-US">Schedule of Weighted Average Remaining Term and Weighted Average Discount Rates</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ScheduleOfWeightedAverageRemainingTermAndWeightedAverageDiscountRatesTableTextBlock" xlink:to="lab_hmh_ScheduleOfWeightedAverageRemainingTermAndWeightedAverageDiscountRatesTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ScheduleOfWeightedAverageRemainingTermAndWeightedAverageDiscountRatesTableTextBlock" xml:lang="en-US">Schedule of weighted average remaining term and weighted average discount rates.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfDebtTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfDebtTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfDebtTableTextBlock" xml:lang="en-US">Schedule of Debt [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfDebtTableTextBlock" xml:lang="en-US">Schedule of short-term and long-term debt</link:label>
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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfMaturitiesOfLongTermDebtTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfMaturitiesOfLongTermDebtTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfMaturitiesOfLongTermDebtTableTextBlock" xml:lang="en-US">Schedule of Maturities of Long-Term Debt [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfMaturitiesOfLongTermDebtTableTextBlock" xml:lang="en-US">Schedule of Maturities of Long-Term Debt</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfMaturitiesOfLongTermDebtTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfMaturitiesOfLongTermDebtTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DisaggregationOfRevenueTableTextBlock" xlink:label="loc_us-gaap_DisaggregationOfRevenueTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DisaggregationOfRevenueTableTextBlock" xml:lang="en-US">Disaggregation of Revenue [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DisaggregationOfRevenueTableTextBlock" xml:lang="en-US">Schedule of Disaggregation of Revenue</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisaggregationOfRevenueTableTextBlock" xlink:to="lab_us-gaap_DisaggregationOfRevenueTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerAssetAndLiabilityTableTextBlock" xlink:label="loc_us-gaap_ContractWithCustomerAssetAndLiabilityTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ContractWithCustomerAssetAndLiabilityTableTextBlock" xml:lang="en-US">Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ContractWithCustomerAssetAndLiabilityTableTextBlock" xml:lang="en-US">Schedule of Change in Contract Assets and Liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ContractWithCustomerAssetAndLiabilityTableTextBlock" xlink:to="lab_us-gaap_ContractWithCustomerAssetAndLiabilityTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfAccruedExpensesTable" xlink:label="loc_hmh_ScheduleOfAccruedExpensesTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfAccruedExpensesTable" xml:lang="en-US">Schedule of Accrued expenses [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ScheduleOfAccruedExpensesTable" xlink:to="lab_hmh_ScheduleOfAccruedExpensesTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock" xml:lang="en-US">Schedule of Accrued Liabilities [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock" xml:lang="en-US">Schedule of Accrued Expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfAccruedLiabilitiesTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock" xml:lang="en-US">Schedule of Product Warranty Liability [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock" xml:lang="en-US">Schedule of Changes to the Company's Warranty Liability</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNoncurrentLiabilitiesTableTextBlock" xlink:label="loc_us-gaap_OtherNoncurrentLiabilitiesTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherNoncurrentLiabilitiesTableTextBlock" xml:lang="en-US">Other Noncurrent Liabilities [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherNoncurrentLiabilitiesTableTextBlock" xml:lang="en-US">Summary Of Other Noncurrent Liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherNoncurrentLiabilitiesTableTextBlock" xlink:to="lab_us-gaap_OtherNoncurrentLiabilitiesTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTextBlock" xlink:label="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTextBlock" xml:lang="en-US">Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTextBlock" xml:lang="en-US">Schedule of Change in Ownership of HMH B.V</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTextBlock" xlink:to="lab_us-gaap_ConsolidationLessThanWhollyOwnedSubsidiaryParentOwnershipInterestEffectsOfChangesNetTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock" xml:lang="en-US">Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock" xml:lang="en-US">Schedule of Accumulated Other Comprehensive Income (Loss)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfAccumulatedOtherComprehensiveIncomeLossTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfNonvestedRestrictedStockUnitsActivityTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfNonvestedRestrictedStockUnitsActivityTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfNonvestedRestrictedStockUnitsActivityTableTextBlock" xml:lang="en-US">Schedule of Nonvested Restricted Stock Units Activity [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfNonvestedRestrictedStockUnitsActivityTableTextBlock" xml:lang="en-US">Summary of RSUs Activity</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfNonvestedRestrictedStockUnitsActivityTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfNonvestedRestrictedStockUnitsActivityTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfNonvestedPerformanceBasedUnitsActivityTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfNonvestedPerformanceBasedUnitsActivityTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfNonvestedPerformanceBasedUnitsActivityTableTextBlock" xml:lang="en-US">Schedule of Nonvested Performance-Based Units Activity [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfNonvestedPerformanceBasedUnitsActivityTableTextBlock" xml:lang="en-US">Summary of PSUs Activity</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfNonvestedPerformanceBasedUnitsActivityTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfNonvestedPerformanceBasedUnitsActivityTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfShareBasedPaymentAwardPerformanceSharesValuationAssumptionsTableTextBlock" xlink:label="loc_hmh_ScheduleOfShareBasedPaymentAwardPerformanceSharesValuationAssumptionsTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfShareBasedPaymentAwardPerformanceSharesValuationAssumptionsTableTextBlock" xml:lang="en-US">Schedule of Share-Based Payment Award, Performance Shares, Valuation Assumptions [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ScheduleOfShareBasedPaymentAwardPerformanceSharesValuationAssumptionsTableTextBlock" xml:lang="en-US">Schedule of PSU Awards Weighted Average Assumptions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ScheduleOfShareBasedPaymentAwardPerformanceSharesValuationAssumptionsTableTextBlock" xlink:to="lab_hmh_ScheduleOfShareBasedPaymentAwardPerformanceSharesValuationAssumptionsTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ScheduleOfShareBasedPaymentAwardPerformanceSharesValuationAssumptionsTableTextBlock" xml:lang="en-US">Schedule of Share-Based Payment Award, Performance Shares, Valuation Assumptions</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:label="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanDisclosureLineItems" xml:lang="en-US">Defined Benefit Plan Disclosure [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanDisclosureLineItems" xlink:to="lab_us-gaap_DefinedBenefitPlanDisclosureLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xml:lang="en-US">Schedule of Net Benefit Costs [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xml:lang="en-US">Schedule of Components of Net Periodic Cost</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xml:lang="en-US">Schedule of Net Periodic Cost Recognized in Selling, General and Administrative Expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock" xlink:label="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock" xml:lang="en-US">Schedule of Defined Benefit Plans Disclosures [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock" xml:lang="en-US">Schedule of The Accumulated Benefit Obligation</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock" xlink:to="lab_us-gaap_ScheduleOfDefinedBenefitPlansDisclosuresTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock" xml:lang="en-US">Schedule of Amounts Recognized in Balance Sheet [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock" xml:lang="en-US">Schedule of The Amounts Recognized in The Consolidated Balance Sheets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAccumulatedBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfAccumulatedBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfAccumulatedBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock" xml:lang="en-US">Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfAccumulatedBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock" xml:lang="en-US">Schedule of The Plans With Projected Benefit Obligations and Accumulated Benefit</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAccumulatedBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfAccumulatedBenefitObligationsInExcessOfFairValueOfPlanAssetsTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xml:lang="en-US">Defined Benefit Plan, Assumptions [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xml:lang="en-US">Schedule of The Weighted Average Assumptions Used To Determine Net Periodic</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAmountsRecognizedInOtherComprehensiveIncomeLossTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfAmountsRecognizedInOtherComprehensiveIncomeLossTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfAmountsRecognizedInOtherComprehensiveIncomeLossTableTextBlock" xml:lang="en-US">Schedule of Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfAmountsRecognizedInOtherComprehensiveIncomeLossTableTextBlock" xml:lang="en-US">Schedule of Amount Recorded Before-Tax in Accumulated Other Comprehensive Income (Loss)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAmountsRecognizedInOtherComprehensiveIncomeLossTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfAmountsRecognizedInOtherComprehensiveIncomeLossTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfCurrentLifeExpectancyAfterRetirementTableTextBlock" xlink:label="loc_hmh_ScheduleOfCurrentLifeExpectancyAfterRetirementTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfCurrentLifeExpectancyAfterRetirementTableTextBlock" xml:lang="en-US">Schedule of Current Life Expectancy After Retirement [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ScheduleOfCurrentLifeExpectancyAfterRetirementTableTextBlock" xml:lang="en-US">Schedule of The Current Life Expectancy After Retirement</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ScheduleOfCurrentLifeExpectancyAfterRetirementTableTextBlock" xlink:to="lab_hmh_ScheduleOfCurrentLifeExpectancyAfterRetirementTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ScheduleOfCurrentLifeExpectancyAfterRetirementTableTextBlock" xml:lang="en-US">Schedule of current life expectancy after retirement.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfEffectOfOnePercentagePointDefinedBenefitObligationTableTextBlock" xlink:label="loc_hmh_ScheduleOfEffectOfOnePercentagePointDefinedBenefitObligationTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfEffectOfOnePercentagePointDefinedBenefitObligationTableTextBlock" xml:lang="en-US">Schedule of Effect of One Percentage Point Defined Benefit Obligation [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ScheduleOfEffectOfOnePercentagePointDefinedBenefitObligationTableTextBlock" xml:lang="en-US">Schedule of The Pension Plans In Norway</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ScheduleOfEffectOfOnePercentagePointDefinedBenefitObligationTableTextBlock" xlink:to="lab_hmh_ScheduleOfEffectOfOnePercentagePointDefinedBenefitObligationTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ScheduleOfEffectOfOnePercentagePointDefinedBenefitObligationTableTextBlock" xml:lang="en-US">Schedule of effect of one percentage point defined benefit obligation.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" xml:lang="en-US">Schedule of Expected Benefit Payments [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" xml:lang="en-US">Schedule of The Expected Benefit Payments For Pension Benefits</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" xml:lang="en-US">Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock" xml:lang="en-US">Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfIncomeBeforeIncomeTaxDomesticAndForeignTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" xml:lang="en-US">Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" xml:lang="en-US">Schedule of Deferred Tax Assets and Liabilities [Table Text Block]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock" xml:lang="en-US">Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfUnrecognizedTaxBenefitsRollForwardTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRestructuringReserveByTypeOfCostTextBlock" xlink:label="loc_us-gaap_ScheduleOfRestructuringReserveByTypeOfCostTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfRestructuringReserveByTypeOfCostTextBlock" xml:lang="en-US">Schedule of Restructuring Reserve by Type of Cost [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfRestructuringReserveByTypeOfCostTextBlock" xml:lang="en-US">Summary of Changes in the Provision Balance for Restructuring and Other Charges</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRestructuringReserveByTypeOfCostTextBlock" xlink:to="lab_us-gaap_ScheduleOfRestructuringReserveByTypeOfCostTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfRelatedPartyTransactionsTableTextBlock" xml:lang="en-US">Schedule of Related Party Transactions [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfRelatedPartyTransactionsTableTextBlock" xml:lang="en-US">Schedule of Related Party Transactions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfRelatedPartyTransactionsTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock" xlink:label="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock" xml:lang="en-US">Segment Reporting, Reconciliation of Revenue by Segment to Consolidated [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock" xml:lang="en-US">Schedule of Reconciliation of Reportable Segment Revenues</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock" xlink:to="lab_us-gaap_ReconciliationOfRevenueFromSegmentsToConsolidatedTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock" xlink:label="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock" xml:lang="en-US">Segment Reporting, Reconciliation of Profit (Loss) by Segment to Consolidated [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock" xml:lang="en-US">Schedule of Reconciliation of Segment Performance</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock" xlink:to="lab_us-gaap_ReconciliationOfOperatingProfitLossFromSegmentsToConsolidatedTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock" xml:lang="en-US">Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock" xml:lang="en-US">Schedule of revenue and long-lived assets on the basis of geography</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsByGeographicalAreasTableTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" xml:lang="en-US">Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" xml:lang="en-US">Schedule of Potential Common Shares Excluded from Diluted Share Calculation</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" xlink:to="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTextBlock" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_AffiliatedEntityMember" xlink:label="loc_srt_AffiliatedEntityMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_AffiliatedEntityMember" xml:lang="en-US">Affiliated Entity [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_AffiliatedEntityMember" xlink:to="lab_srt_AffiliatedEntityMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" xlink:label="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" xml:lang="en-US">Sale of Stock, Number of Shares Issued in Transaction</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" xml:lang="en-US">Shares issued (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" xlink:to="lab_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharesIssuedPricePerShare" xlink:label="loc_us-gaap_SharesIssuedPricePerShare" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SharesIssuedPricePerShare" xml:lang="en-US">Shares Issued, Price Per Share</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SharesIssuedPricePerShare" xml:lang="en-US">Shares issued, price per share</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharesIssuedPricePerShare" xlink:to="lab_us-gaap_SharesIssuedPricePerShare" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:label="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xml:lang="en-US">Sale of Stock, Consideration Received on Transaction</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xml:lang="en-US">Net proceeds</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:to="lab_us-gaap_SaleOfStockConsiderationReceivedOnTransaction" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SubsidiarySaleOfStockAxis" xml:lang="en-US">Sale of Stock [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SubsidiarySaleOfStockAxis" xml:lang="en-US">Sale of Stock [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis" xlink:to="lab_us-gaap_SubsidiarySaleOfStockAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SaleOfStockNameOfTransactionDomain" xml:lang="en-US">Sale of Stock [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SaleOfStockNameOfTransactionDomain" xml:lang="en-US">Sale of Stock [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain" xlink:to="lab_us-gaap_SaleOfStockNameOfTransactionDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IPOMember" xlink:label="loc_us-gaap_IPOMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IPOMember" xml:lang="en-US">IPO [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IPOMember" xml:lang="en-US">IPO</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IPOMember" xlink:to="lab_us-gaap_IPOMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_UnderwritersMember" xlink:label="loc_hmh_UnderwritersMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_UnderwritersMember" xml:lang="en-US">Underwriters [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_UnderwritersMember" xlink:to="lab_hmh_UnderwritersMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockRepurchasedDuringPeriodShares" xlink:label="loc_us-gaap_StockRepurchasedDuringPeriodShares" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockRepurchasedDuringPeriodShares" xml:lang="en-US">Stock Repurchased During Period, Shares</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockRepurchasedDuringPeriodShares" xml:lang="en-US">Repurchased to satisfy employee's tax holding obligations (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockRepurchasedDuringPeriodShares" xlink:to="lab_us-gaap_StockRepurchasedDuringPeriodShares" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SaleOfStockPricePerShare" xlink:label="loc_us-gaap_SaleOfStockPricePerShare" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SaleOfStockPricePerShare" xml:lang="en-US">Sale of Stock, Price Per Share</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleOfStockPricePerShare" xlink:to="lab_us-gaap_SaleOfStockPricePerShare" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterestOwnershipPercentageByParent" xlink:label="loc_us-gaap_MinorityInterestOwnershipPercentageByParent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MinorityInterestOwnershipPercentageByParent" xml:lang="en-US">Subsidiary, Ownership Percentage, Parent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_MinorityInterestOwnershipPercentageByParent" xml:lang="en-US">Equity interest percentage</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_MinorityInterestOwnershipPercentageByParent" xml:lang="en-US">Ownership percentage</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MinorityInterestOwnershipPercentageByParent" xlink:to="lab_us-gaap_MinorityInterestOwnershipPercentageByParent" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_SubsidiaryVotingPowerPercentage" xlink:label="loc_hmh_SubsidiaryVotingPowerPercentage" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_SubsidiaryVotingPowerPercentage" xml:lang="en-US">Subsidiary, Voting Power Percentage</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_SubsidiaryVotingPowerPercentage" xml:lang="en-US">Voting power percentage</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_SubsidiaryVotingPowerPercentage" xlink:to="lab_hmh_SubsidiaryVotingPowerPercentage" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_SubsidiaryVotingPowerPercentage" xml:lang="en-US">Subsidiary, Voting Power Percentage</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipAxis" xlink:label="loc_srt_OwnershipAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_OwnershipAxis" xml:lang="en-US">Ownership [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_OwnershipAxis" xml:lang="en-US">Ownership [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_OwnershipAxis" xlink:to="lab_srt_OwnershipAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_OwnershipDomain" xlink:label="loc_srt_OwnershipDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_OwnershipDomain" xml:lang="en-US">Ownership [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_OwnershipDomain" xml:lang="en-US">Ownership [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_OwnershipDomain" xlink:to="lab_srt_OwnershipDomain" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_CompanyAndNonControllingInterestsMember" xlink:label="loc_hmh_CompanyAndNonControllingInterestsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_CompanyAndNonControllingInterestsMember" xml:lang="en-US">Company and Non controlling Interests [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_CompanyAndNonControllingInterestsMember" xlink:to="lab_hmh_CompanyAndNonControllingInterestsMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTable" xlink:label="loc_us-gaap_ConcentrationRiskTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ConcentrationRiskTable" xml:lang="en-US">Concentration Risk [Table]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ConcentrationRiskTable" xml:lang="en-US">Concentration Risk [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskTable" xlink:to="lab_us-gaap_ConcentrationRiskTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByTypeAxis" xlink:label="loc_us-gaap_ConcentrationRiskByTypeAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ConcentrationRiskByTypeAxis" xml:lang="en-US">Concentration Risk Type [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ConcentrationRiskByTypeAxis" xml:lang="en-US">Concentration Risk Type [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskByTypeAxis" xlink:to="lab_us-gaap_ConcentrationRiskByTypeAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskTypeDomain" xlink:label="loc_us-gaap_ConcentrationRiskTypeDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ConcentrationRiskTypeDomain" xml:lang="en-US">Concentration Risk Type [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ConcentrationRiskTypeDomain" xml:lang="en-US">Concentration Risk Type [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskTypeDomain" xlink:to="lab_us-gaap_ConcentrationRiskTypeDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CustomerConcentrationRiskMember" xlink:label="loc_us-gaap_CustomerConcentrationRiskMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CustomerConcentrationRiskMember" xml:lang="en-US">Customer Concentration Risk [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CustomerConcentrationRiskMember" xml:lang="en-US">Customer Concentration Risk</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CustomerConcentrationRiskMember" xlink:to="lab_us-gaap_CustomerConcentrationRiskMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:label="loc_us-gaap_ConcentrationRiskByBenchmarkAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ConcentrationRiskByBenchmarkAxis" xml:lang="en-US">Concentration Risk Benchmark [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ConcentrationRiskByBenchmarkAxis" xml:lang="en-US">Concentration Risk Benchmark [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:to="lab_us-gaap_ConcentrationRiskByBenchmarkAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskBenchmarkDomain" xlink:label="loc_us-gaap_ConcentrationRiskBenchmarkDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ConcentrationRiskBenchmarkDomain" xml:lang="en-US">Concentration Risk Benchmark [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ConcentrationRiskBenchmarkDomain" xml:lang="en-US">Concentration Risk Benchmark [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskBenchmarkDomain" xlink:to="lab_us-gaap_ConcentrationRiskBenchmarkDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueFromContractWithCustomerMember" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerMember" xml:lang="en-US">Revenue from Contract with Customer Benchmark [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RevenueFromContractWithCustomerMember" xml:lang="en-US">Revenue</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueFromContractWithCustomerMember" xlink:to="lab_us-gaap_RevenueFromContractWithCustomerMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableMember" xlink:label="loc_us-gaap_AccountsReceivableMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccountsReceivableMember" xml:lang="en-US">Accounts Receivable [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AccountsReceivableMember" xml:lang="en-US">Accounts Receivable</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsReceivableMember" xlink:to="lab_us-gaap_AccountsReceivableMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MajorCustomersAxis" xlink:label="loc_srt_MajorCustomersAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_MajorCustomersAxis" xml:lang="en-US">Customer [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_MajorCustomersAxis" xml:lang="en-US">Customer [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_MajorCustomersAxis" xlink:to="lab_srt_MajorCustomersAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_NameOfMajorCustomerDomain" xlink:label="loc_srt_NameOfMajorCustomerDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_NameOfMajorCustomerDomain" xml:lang="en-US">Customer [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_NameOfMajorCustomerDomain" xml:lang="en-US">Customer [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_NameOfMajorCustomerDomain" xlink:to="lab_srt_NameOfMajorCustomerDomain" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_CustomerOneMember" xlink:label="loc_hmh_CustomerOneMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_CustomerOneMember" xml:lang="en-US">Customer One [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_CustomerOneMember" xml:lang="en-US">Customer One</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_CustomerOneMember" xlink:to="lab_hmh_CustomerOneMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_CustomerOneMember" xml:lang="en-US">Customer One</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_CustomerTwoMember" xlink:label="loc_hmh_CustomerTwoMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_CustomerTwoMember" xml:lang="en-US">Customer Two [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_CustomerTwoMember" xml:lang="en-US">Customer Two</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_CustomerTwoMember" xlink:to="lab_hmh_CustomerTwoMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_CustomerTwoMember" xml:lang="en-US">Customer Two</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OverAllotmentOptionMember" xlink:label="loc_us-gaap_OverAllotmentOptionMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OverAllotmentOptionMember" xml:lang="en-US">Over-Allotment Option [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OverAllotmentOptionMember" xml:lang="en-US">Over-Allotment Option</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OverAllotmentOptionMember" xlink:to="lab_us-gaap_OverAllotmentOptionMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_BakerHughesHoldingsLLCMember" xlink:label="loc_hmh_BakerHughesHoldingsLLCMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_BakerHughesHoldingsLLCMember" xml:lang="en-US">Baker Hughes Holdings LLC [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_BakerHughesHoldingsLLCMember" xml:lang="en-US">Baker Hughes Holdings LLC</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_BakerHughesHoldingsLLCMember" xlink:to="lab_hmh_BakerHughesHoldingsLLCMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_BakerHughesHoldingsLLCMember" xml:lang="en-US">Baker Hughes Holdings LLC</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AkastorASMember" xlink:label="loc_hmh_AkastorASMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AkastorASMember" xml:lang="en-US">Akastor AS [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_AkastorASMember" xml:lang="en-US">Akastor AS [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AkastorASMember" xlink:to="lab_hmh_AkastorASMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AkastorASMember" xml:lang="en-US">Akastor AS</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_MercuryHoldCoIncMember" xlink:label="loc_hmh_MercuryHoldCoIncMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_MercuryHoldCoIncMember" xml:lang="en-US">Mercury HoldCo Inc. [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_MercuryHoldCoIncMember" xml:lang="en-US">Mercury HoldCo Inc.</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_MercuryHoldCoIncMember" xlink:to="lab_hmh_MercuryHoldCoIncMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_MercuryHoldCoIncMember" xml:lang="en-US">Mercury HoldCo Inc.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_BakerHughesAndAkastorMember" xlink:label="loc_hmh_BakerHughesAndAkastorMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_BakerHughesAndAkastorMember" xml:lang="en-US">Baker Hughes And Akastor [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_BakerHughesAndAkastorMember" xml:lang="en-US">Baker Hughes And Akastor</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_BakerHughesAndAkastorMember" xlink:to="lab_hmh_BakerHughesAndAkastorMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_BakerHughesAndAkastorMember" xml:lang="en-US">Baker Hughes And Akastor</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_IPOInvestorsMember" xlink:label="loc_hmh_IPOInvestorsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_IPOInvestorsMember" xml:lang="en-US">IPO Investors [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_IPOInvestorsMember" xml:lang="en-US">IPO Investors</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_IPOInvestorsMember" xlink:to="lab_hmh_IPOInvestorsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_IPOInvestorsMember" xml:lang="en-US">IPO Investors</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_HMHBVMember" xlink:label="loc_hmh_HMHBVMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_HMHBVMember" xml:lang="en-US">HMH B.V. [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_HMHBVMember" xml:lang="en-US">HMH B.V. [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_HMHBVMember" xlink:to="lab_hmh_HMHBVMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_HMHBVMember" xml:lang="en-US">HMH B.V.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_HydrilPCBLimitedMember" xlink:label="loc_hmh_HydrilPCBLimitedMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_HydrilPCBLimitedMember" xml:lang="en-US">Hydril PCB Limited [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_HydrilPCBLimitedMember" xlink:to="lab_hmh_HydrilPCBLimitedMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_CounterpartyNameAxis" xlink:label="loc_srt_CounterpartyNameAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_CounterpartyNameAxis" xml:lang="en-US">Counterparty Name [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_CounterpartyNameAxis" xml:lang="en-US">Counterparty Name [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_CounterpartyNameAxis" xlink:to="lab_srt_CounterpartyNameAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RepurchaseAgreementCounterpartyNameDomain" xlink:label="loc_srt_RepurchaseAgreementCounterpartyNameDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_RepurchaseAgreementCounterpartyNameDomain" xml:lang="en-US">Counterparty Name [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_RepurchaseAgreementCounterpartyNameDomain" xml:lang="en-US">Counterparty Name [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RepurchaseAgreementCounterpartyNameDomain" xlink:to="lab_srt_RepurchaseAgreementCounterpartyNameDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskLineItems" xlink:label="loc_us-gaap_ConcentrationRiskLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ConcentrationRiskLineItems" xml:lang="en-US">Concentration Risk [Line Items]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ConcentrationRiskLineItems" xml:lang="en-US">Concentration Risk [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskLineItems" xlink:to="lab_us-gaap_ConcentrationRiskLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners" xlink:label="loc_us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners" xml:lang="en-US">Subsidiary, Ownership Percentage, Noncontrolling Owner</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners" xml:lang="en-US">Equity interest percentage</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners" xlink:to="lab_us-gaap_MinorityInterestOwnershipPercentageByNoncontrollingOwners" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredCostsCurrent" xlink:label="loc_us-gaap_DeferredCostsCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredCostsCurrent" xml:lang="en-US">Deferred Costs, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredCostsCurrent" xml:lang="en-US">Deferred offering costs</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredCostsCurrent" xlink:to="lab_us-gaap_DeferredCostsCurrent" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ShareBasedPaymentArrangementNoncashExpensePreIPO" xlink:label="loc_hmh_ShareBasedPaymentArrangementNoncashExpensePreIPO" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ShareBasedPaymentArrangementNoncashExpensePreIPO" xml:lang="en-US">Share-Based Payment Arrangement, Noncash Expense, Pre-IPO</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ShareBasedPaymentArrangementNoncashExpensePreIPO" xml:lang="en-US">Pre-IPO stock-based compensation expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ShareBasedPaymentArrangementNoncashExpensePreIPO" xlink:to="lab_hmh_ShareBasedPaymentArrangementNoncashExpensePreIPO" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ShareBasedPaymentArrangementNoncashExpensePreIPO" xml:lang="en-US">Share-Based Payment Arrangement, Noncash Expense, Pre-IPO</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConcentrationRiskPercentage1" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ConcentrationRiskPercentage1" xml:lang="en-US">Concentration Risk, Percentage</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ConcentrationRiskPercentage1" xml:lang="en-US">Concentration risk, percentage</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskPercentage1" xlink:to="lab_us-gaap_ConcentrationRiskPercentage1" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccountsReceivableNet" xlink:label="loc_us-gaap_AccountsReceivableNet" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccountsReceivableNet" xml:lang="en-US">Accounts Receivable, after Allowance for Credit Loss</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AccountsReceivableNet" xml:lang="en-US">Account receivable</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountsReceivableNet" xlink:to="lab_us-gaap_AccountsReceivableNet" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AociLossCashFlowHedgeCumulativeGainLossAfterTax" xlink:label="loc_us-gaap_AociLossCashFlowHedgeCumulativeGainLossAfterTax" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AociLossCashFlowHedgeCumulativeGainLossAfterTax" xml:lang="en-US">AOCI, Cash Flow Hedge, Cumulative Gain (Loss), after Tax</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AociLossCashFlowHedgeCumulativeGainLossAfterTax" xml:lang="en-US">Aoci, cash flow hedge, cumulative gain (loss), after tax</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AociLossCashFlowHedgeCumulativeGainLossAfterTax" xlink:to="lab_us-gaap_AociLossCashFlowHedgeCumulativeGainLossAfterTax" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf" xlink:label="loc_us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf" xml:lang="en-US">Impairment of Long-Lived Assets to be Disposed of</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf" xml:lang="en-US">Impairment of long-lived assets to be disposed of</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf" xlink:to="lab_us-gaap_ImpairmentOfLongLivedAssetsToBeDisposedOf" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GoodwillImpairmentLoss" xlink:label="loc_us-gaap_GoodwillImpairmentLoss" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GoodwillImpairmentLoss" xml:lang="en-US">Goodwill, Impairment Loss</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_GoodwillImpairmentLoss" xml:lang="en-US">Goodwill, impairment loss</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillImpairmentLoss" xlink:to="lab_us-gaap_GoodwillImpairmentLoss" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateContinuingOperations" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperations" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Percent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperations" xml:lang="en-US">Effective tax rate</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateContinuingOperations" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateContinuingOperations" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationConsiderationTransferred1" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationConsiderationTransferred1" xml:lang="en-US">Business Combination, Consideration Transferred</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationConsiderationTransferred1" xml:lang="en-US">Total consideration</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_BusinessCombinationConsiderationTransferred1" xml:lang="en-US">Business combination, consideration transferred</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationConsiderationTransferred1" xlink:to="lab_us-gaap_BusinessCombinationConsiderationTransferred1" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_UpfrontConsideration" xlink:label="loc_hmh_UpfrontConsideration" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_UpfrontConsideration" xml:lang="en-US">Upfront Consideration</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_UpfrontConsideration" xml:lang="en-US">Upfront consideration</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_UpfrontConsideration" xlink:to="lab_hmh_UpfrontConsideration" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_UpfrontConsideration" xml:lang="en-US">Upfront consideration.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DeferredConsideration" xlink:label="loc_hmh_DeferredConsideration" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DeferredConsideration" xml:lang="en-US">Deferred Consideration</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_DeferredConsideration" xml:lang="en-US">Deferred consideration</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DeferredConsideration" xlink:to="lab_hmh_DeferredConsideration" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DeferredConsideration" xml:lang="en-US">Deferred consideration.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_Cash" xlink:label="loc_us-gaap_Cash" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_Cash" xml:lang="en-US">Cash</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_Cash" xml:lang="en-US">Company recognized cash</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Cash" xlink:to="lab_us-gaap_Cash" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths" xlink:label="loc_us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths" xml:lang="en-US">Cash Flow Hedge Gain (Loss) to be Reclassified within 12 Months</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths" xml:lang="en-US">Cash Flow Hedge Gain (Loss) to be Reclassified within 12 Months</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths" xlink:to="lab_us-gaap_CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis" xml:lang="en-US">Long-Lived Asset, Class [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentByTypeAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain" xml:lang="en-US">Long-Lived Asset, Class [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentTypeDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentMember" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentMember" xml:lang="en-US">Property, Plant and Equipment [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentMember" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByAssetClassAxis" xlink:label="loc_us-gaap_FairValueByAssetClassAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueByAssetClassAxis" xml:lang="en-US">Asset Class [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueByAssetClassAxis" xlink:to="lab_us-gaap_FairValueByAssetClassAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xml:lang="en-US">Asset Class [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:to="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GoodwillMember" xlink:label="loc_us-gaap_GoodwillMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GoodwillMember" xml:lang="en-US">Goodwill [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillMember" xlink:to="lab_us-gaap_GoodwillMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeAxis" xlink:label="loc_srt_RangeAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_RangeAxis" xml:lang="en-US">Statistical Measurement [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_RangeAxis" xml:lang="en-US">Statistical Measurement [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RangeAxis" xlink:to="lab_srt_RangeAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_RangeMember" xml:lang="en-US">Statistical Measurement [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_RangeMember" xml:lang="en-US">Statistical Measurement [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RangeMember" xlink:to="lab_srt_RangeMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MinimumMember" xlink:label="loc_srt_MinimumMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_MinimumMember" xml:lang="en-US">Minimum [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_MinimumMember" xml:lang="en-US">Minimum</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_MinimumMember" xlink:to="lab_srt_MinimumMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeAbstract" xlink:label="loc_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeAbstract" xml:lang="en-US">Schedule of Property Plant And Equipment Useful Life [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeAbstract" xlink:to="lab_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeAbstract" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTable" xlink:label="loc_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTable" xml:lang="en-US">Schedule of Property Plant And Equipment Useful Life [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTable" xlink:to="lab_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeLineItems" xlink:label="loc_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeLineItems" xml:lang="en-US">Schedule of Property Plant And Equipment Useful Life [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeLineItems" xlink:to="lab_hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife" xml:lang="en-US">Property, Plant, and Equipment, Useful Life</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife" xml:lang="en-US">Property, plant, and Equipment, useful life</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentUsefulLife" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BuildingMember" xlink:label="loc_us-gaap_BuildingMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BuildingMember" xml:lang="en-US">Building [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BuildingMember" xlink:to="lab_us-gaap_BuildingMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MachineryAndEquipmentMember" xlink:label="loc_us-gaap_MachineryAndEquipmentMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MachineryAndEquipmentMember" xml:lang="en-US">Machinery and Equipment [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_MachineryAndEquipmentMember" xml:lang="en-US">Machinery, equipment and software [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MachineryAndEquipmentMember" xlink:to="lab_us-gaap_MachineryAndEquipmentMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_MaximumMember" xlink:label="loc_srt_MaximumMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_MaximumMember" xml:lang="en-US">Maximum [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_MaximumMember" xml:lang="en-US">Maximum</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_MaximumMember" xlink:to="lab_srt_MaximumMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_CurrentPrepaidExpenseAndOtherAssets" xlink:label="loc_hmh_CurrentPrepaidExpenseAndOtherAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_CurrentPrepaidExpenseAndOtherAssets" xml:lang="en-US">Current Prepaid Expense and Other Assets</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_CurrentPrepaidExpenseAndOtherAssets" xml:lang="en-US">Prepaids and other current assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_CurrentPrepaidExpenseAndOtherAssets" xlink:to="lab_hmh_CurrentPrepaidExpenseAndOtherAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_CurrentPrepaidExpenseAndOtherAssets" xml:lang="en-US">Current prepaid expense and other assets.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_PercentageOfOwnershipInterestHeldByParent" xlink:label="loc_hmh_PercentageOfOwnershipInterestHeldByParent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_PercentageOfOwnershipInterestHeldByParent" xml:lang="en-US">Percentage Of Ownership Interest Held By Parent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_PercentageOfOwnershipInterestHeldByParent" xml:lang="en-US">Percentage of ownership interest held by parent</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_PercentageOfOwnershipInterestHeldByParent" xlink:to="lab_hmh_PercentageOfOwnershipInterestHeldByParent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_PercentageOfOwnershipInterestHeldByParent" xml:lang="en-US">Percentage of ownership interest held by parent.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_NonControllingInterest" xlink:label="loc_hmh_NonControllingInterest" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_NonControllingInterest" xml:lang="en-US">Non controlling Interest</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_NonControllingInterest" xml:lang="en-US">Non-controlling interests</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_NonControllingInterest" xlink:to="lab_hmh_NonControllingInterest" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_NonControllingInterest" xml:lang="en-US">Non controlling interest.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_PercentageOfEconomicInterestHeldByPrincipalStockholder" xlink:label="loc_hmh_PercentageOfEconomicInterestHeldByPrincipalStockholder" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_PercentageOfEconomicInterestHeldByPrincipalStockholder" xml:lang="en-US">Percentage Of Economic Interest Held By Principal Stockholder</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_PercentageOfEconomicInterestHeldByPrincipalStockholder" xml:lang="en-US">Percentage of economic interest held by principal stockholder</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_PercentageOfEconomicInterestHeldByPrincipalStockholder" xlink:to="lab_hmh_PercentageOfEconomicInterestHeldByPrincipalStockholder" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_PercentageOfEconomicInterestHeldByPrincipalStockholder" xml:lang="en-US">Percentage of economic interest held by principal stockholder.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AdditionalPaidInCapitals" xlink:label="loc_hmh_AdditionalPaidInCapitals" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AdditionalPaidInCapitals" xml:lang="en-US">Additional Paid in Capitals</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_AdditionalPaidInCapitals" xml:lang="en-US">Additional paid-in capital</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AdditionalPaidInCapitals" xlink:to="lab_hmh_AdditionalPaidInCapitals" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AdditionalPaidInCapitals" xml:lang="en-US">Additional Paid in Capitals.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_PercentageOfPaymentByPrincipalStockholders" xlink:label="loc_hmh_PercentageOfPaymentByPrincipalStockholders" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_PercentageOfPaymentByPrincipalStockholders" xml:lang="en-US">Percentage Of Payment By Principal Stockholders</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_PercentageOfPaymentByPrincipalStockholders" xml:lang="en-US">Percentage of payment by principal stockholders</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_PercentageOfPaymentByPrincipalStockholders" xlink:to="lab_hmh_PercentageOfPaymentByPrincipalStockholders" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_PercentageOfPaymentByPrincipalStockholders" xml:lang="en-US">Percentage of payment by principal stockholders.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AmountOfTaxReceivableAgreement" xlink:label="loc_hmh_AmountOfTaxReceivableAgreement" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AmountOfTaxReceivableAgreement" xml:lang="en-US">Amount Of Tax Receivable Agreement</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_AmountOfTaxReceivableAgreement" xml:lang="en-US">Amount of tax receivable agreement</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AmountOfTaxReceivableAgreement" xlink:to="lab_hmh_AmountOfTaxReceivableAgreement" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AmountOfTaxReceivableAgreement" xml:lang="en-US">Amount of tax receivable agreement.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AmountOfPrincipalStockholdersTaxReceivableAgreement" xlink:label="loc_hmh_AmountOfPrincipalStockholdersTaxReceivableAgreement" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AmountOfPrincipalStockholdersTaxReceivableAgreement" xml:lang="en-US">Amount Of Principal Stockholders Tax Receivable Agreement</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_AmountOfPrincipalStockholdersTaxReceivableAgreement" xml:lang="en-US">Amount of principal stockholders tax receivable agreement</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AmountOfPrincipalStockholdersTaxReceivableAgreement" xlink:to="lab_hmh_AmountOfPrincipalStockholdersTaxReceivableAgreement" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AmountOfPrincipalStockholdersTaxReceivableAgreement" xml:lang="en-US">Amount of principal stockholders tax receivable agreement.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxAssetsNet" xlink:label="loc_us-gaap_DeferredTaxAssetsNet" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredTaxAssetsNet" xml:lang="en-US">Deferred Tax Assets, Net of Valuation Allowance</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredTaxAssetsNet" xml:lang="en-US">Deferred tax asset</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_DeferredTaxAssetsNet" xml:lang="en-US">Deferred tax asset</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_DeferredTaxAssetsNet" xml:lang="en-US">Total deferred tax asset after valuation allowance</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsNet" xlink:to="lab_us-gaap_DeferredTaxAssetsNet" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_NoncurrentLiabilities" xlink:label="loc_hmh_NoncurrentLiabilities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_NoncurrentLiabilities" xml:lang="en-US">Noncurrent Liabilities</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_NoncurrentLiabilities" xml:lang="en-US">Liabilities, Noncurrent</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_NoncurrentLiabilities" xlink:to="lab_hmh_NoncurrentLiabilities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_NoncurrentLiabilities" xml:lang="en-US">Noncurrent liabilities.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_StateCorporateTaxRate" xlink:label="loc_hmh_StateCorporateTaxRate" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_StateCorporateTaxRate" xml:lang="en-US">State Corporate Tax Rate</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_StateCorporateTaxRate" xml:lang="en-US">State corporate tax rate</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_StateCorporateTaxRate" xlink:to="lab_hmh_StateCorporateTaxRate" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_StateCorporateTaxRate" xml:lang="en-US">State corporate tax rate.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProceedsFromIssuanceInitialPublicOffering" xlink:label="loc_us-gaap_ProceedsFromIssuanceInitialPublicOffering" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProceedsFromIssuanceInitialPublicOffering" xml:lang="en-US">Proceeds from Issuance Initial Public Offering</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ProceedsFromIssuanceInitialPublicOffering" xml:lang="en-US">Proceeds from Issuance Initial Public Offering</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromIssuanceInitialPublicOffering" xlink:to="lab_us-gaap_ProceedsFromIssuanceInitialPublicOffering" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NoninterestExpenseOfferingCost" xlink:label="loc_us-gaap_NoninterestExpenseOfferingCost" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NoninterestExpenseOfferingCost" xml:lang="en-US">Offering Cost, Expense</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NoninterestExpenseOfferingCost" xml:lang="en-US">Offering cost, expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoninterestExpenseOfferingCost" xlink:to="lab_us-gaap_NoninterestExpenseOfferingCost" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_RepaymentsOfShareholderLoan" xlink:label="loc_hmh_RepaymentsOfShareholderLoan" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_RepaymentsOfShareholderLoan" xml:lang="en-US">Repayments of Shareholder Loan</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_RepaymentsOfShareholderLoan" xml:lang="en-US">Repayments of shareholder loan</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_RepaymentsOfShareholderLoan" xlink:to="lab_hmh_RepaymentsOfShareholderLoan" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_RepaymentsOfShareholderLoan" xml:lang="en-US">Repayments of shareholder loan.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ProceedsFromShareholderLoan" xlink:label="loc_hmh_ProceedsFromShareholderLoan" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ProceedsFromShareholderLoan" xml:lang="en-US">Proceeds From Shareholder Loan</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ProceedsFromShareholderLoan" xml:lang="en-US">Proceeds from shareholder loan</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ProceedsFromShareholderLoan" xlink:to="lab_hmh_ProceedsFromShareholderLoan" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ProceedsFromShareholderLoan" xml:lang="en-US">Proceeds from shareholder loan.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AllocatedShareBasedCompensationExpense" xlink:label="loc_us-gaap_AllocatedShareBasedCompensationExpense" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AllocatedShareBasedCompensationExpense" xml:lang="en-US">Share-Based Payment Arrangement, Expense</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_AllocatedShareBasedCompensationExpense" xml:lang="en-US">Share-based payment arrangement, expense</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AllocatedShareBasedCompensationExpense" xml:lang="en-US">Share-based compensation</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AllocatedShareBasedCompensationExpense" xlink:to="lab_us-gaap_AllocatedShareBasedCompensationExpense" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestExpense" xlink:label="loc_us-gaap_InterestExpense" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InterestExpense" xml:lang="en-US">Interest Expense, Operating and Nonoperating</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_InterestExpense" xml:lang="en-US">Interest expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestExpense" xlink:to="lab_us-gaap_InterestExpense" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestIncomeOperating" xlink:label="loc_us-gaap_InterestIncomeOperating" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InterestIncomeOperating" xml:lang="en-US">Interest Income, Operating</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_InterestIncomeOperating" xml:lang="en-US">Interest income</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestIncomeOperating" xlink:to="lab_us-gaap_InterestIncomeOperating" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityNoteSubscriptionsReceivable" xlink:label="loc_us-gaap_StockholdersEquityNoteSubscriptionsReceivable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockholdersEquityNoteSubscriptionsReceivable" xml:lang="en-US">Stockholders' Equity Note, Subscriptions Receivable</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockholdersEquityNoteSubscriptionsReceivable" xml:lang="en-US">Stockholders' equity note, subscriptions receivable</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityNoteSubscriptionsReceivable" xlink:to="lab_us-gaap_StockholdersEquityNoteSubscriptionsReceivable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_SubsidiaryAxis" xlink:label="loc_hmh_SubsidiaryAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_SubsidiaryAxis" xml:lang="en-US">Subsidiary [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_SubsidiaryAxis" xlink:to="lab_hmh_SubsidiaryAxis" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_SubsidiaryDomain" xlink:label="loc_hmh_SubsidiaryDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_SubsidiaryDomain" xml:lang="en-US">Subsidiary [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_SubsidiaryDomain" xlink:to="lab_hmh_SubsidiaryDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncrementalCommonSharesAttributableToEquityUnitPurchaseAgreements" xlink:label="loc_us-gaap_IncrementalCommonSharesAttributableToEquityUnitPurchaseAgreements" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncrementalCommonSharesAttributableToEquityUnitPurchaseAgreements" xml:lang="en-US">Incremental Common Shares Attributable to Dilutive Effect of Equity Unit Purchase Agreements</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncrementalCommonSharesAttributableToEquityUnitPurchaseAgreements" xml:lang="en-US">Incremental common shares attributable to dilutive securities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncrementalCommonSharesAttributableToEquityUnitPurchaseAgreements" xlink:to="lab_us-gaap_IncrementalCommonSharesAttributableToEquityUnitPurchaseAgreements" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BasicEarningsPerShareProForma" xlink:label="loc_us-gaap_BasicEarningsPerShareProForma" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BasicEarningsPerShareProForma" xml:lang="en-US">Basic Earnings Per Share, Pro Forma</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BasicEarningsPerShareProForma" xml:lang="en-US">Earnings per share &#8211; basic</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BasicEarningsPerShareProForma" xlink:to="lab_us-gaap_BasicEarningsPerShareProForma" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DilutedEarningsPerShareProForma" xlink:label="loc_us-gaap_DilutedEarningsPerShareProForma" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DilutedEarningsPerShareProForma" xml:lang="en-US">Diluted Earnings Per Share Pro Forma</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DilutedEarningsPerShareProForma" xml:lang="en-US">Earnings per share &#8211; diluted</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DilutedEarningsPerShareProForma" xlink:to="lab_us-gaap_DilutedEarningsPerShareProForma" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationsAbstract" xlink:label="loc_us-gaap_BusinessCombinationsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationsAbstract" xml:lang="en-US">Business Combination [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationsAbstract" xlink:to="lab_us-gaap_BusinessCombinationsAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsToAcquireBusinessesGross" xlink:label="loc_us-gaap_PaymentsToAcquireBusinessesGross" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PaymentsToAcquireBusinessesGross" xml:lang="en-US">Payments to Acquire Businesses, Gross</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_PaymentsToAcquireBusinessesGross" xml:lang="en-US">Cash</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PaymentsToAcquireBusinessesGross" xml:lang="en-US">Cash consideration paid, including &#163;0.2 million cash acquired</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquireBusinessesGross" xlink:to="lab_us-gaap_PaymentsToAcquireBusinessesGross" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationContingentConsiderationAsset" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationAsset" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationContingentConsiderationAsset" xml:lang="en-US">Business Combination, Contingent Consideration, Asset</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationContingentConsiderationAsset" xml:lang="en-US">Contingent consideration</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationContingentConsiderationAsset" xlink:to="lab_us-gaap_BusinessCombinationContingentConsiderationAsset" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_WarrantLiabilities" xlink:label="loc_hmh_WarrantLiabilities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_WarrantLiabilities" xml:lang="en-US">Warrant Liabilities</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_WarrantLiabilities" xml:lang="en-US">Warrant liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_WarrantLiabilities" xlink:to="lab_hmh_WarrantLiabilities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_WarrantLiabilities" xml:lang="en-US">Warrant liabilities.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_MaximumContingentConsideration" xlink:label="loc_hmh_MaximumContingentConsideration" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_MaximumContingentConsideration" xml:lang="en-US">Maximum Contingent Consideration</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_MaximumContingentConsideration" xml:lang="en-US">Maximum contingent consideration</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_MaximumContingentConsideration" xlink:to="lab_hmh_MaximumContingentConsideration" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_MaximumContingentConsideration" xml:lang="en-US">Maximum contingent consideration.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_UndiscountedContingentConsideration" xlink:label="loc_hmh_UndiscountedContingentConsideration" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_UndiscountedContingentConsideration" xml:lang="en-US">Undiscounted Contingent Consideration</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_UndiscountedContingentConsideration" xml:lang="en-US">Asset acquisition, consideration transferred, contingent consideration</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_UndiscountedContingentConsideration" xlink:to="lab_hmh_UndiscountedContingentConsideration" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_UndiscountedContingentConsideration" xml:lang="en-US">Undiscounted contingent consideration.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts" xlink:label="loc_us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts" xml:lang="en-US">Business Combination, Transaction Cost, Excluding Separately Recognized Transaction</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts" xml:lang="en-US">Business combination, transaction cost, excluding separately recognized transaction</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts" xlink:to="lab_us-gaap_BusinessAcquisitionCostOfAcquiredEntityTransactionCosts" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationContingentConsiderationLiability" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiability" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationContingentConsiderationLiability" xml:lang="en-US">Business Combination, Contingent Consideration, Liability</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationContingentConsiderationLiability" xml:lang="en-US">Contingent consideration</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationContingentConsiderationLiability" xlink:to="lab_us-gaap_BusinessCombinationContingentConsiderationLiability" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill" xml:lang="en-US">Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Excluding Goodwill</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill" xml:lang="en-US">Identified intangible assets acquired</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill" xml:lang="en-US">Intangible assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill" xlink:to="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedIntangibleAssetsOtherThanGoodwill" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xml:lang="en-US">Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xml:lang="en-US">Cash and cash equivalents</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" xlink:to="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCashAndEquivalents" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GoodwillPurchaseAccountingAdjustments" xlink:label="loc_us-gaap_GoodwillPurchaseAccountingAdjustments" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GoodwillPurchaseAccountingAdjustments" xml:lang="en-US">Goodwill, Measurement Period Adjustment</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_GoodwillPurchaseAccountingAdjustments" xml:lang="en-US">Purchase price adjustment</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_GoodwillPurchaseAccountingAdjustments" xml:lang="en-US">Purchase price adjustment</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillPurchaseAccountingAdjustments" xlink:to="lab_us-gaap_GoodwillPurchaseAccountingAdjustments" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAxis" xlink:label="loc_us-gaap_BusinessAcquisitionAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionAxis" xml:lang="en-US">Business Combination [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessAcquisitionAxis" xml:lang="en-US">Business Combination [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionAxis" xlink:to="lab_us-gaap_BusinessAcquisitionAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionAcquireeDomain" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionAcquireeDomain" xml:lang="en-US">Business Combination [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessAcquisitionAcquireeDomain" xml:lang="en-US">Business Combination [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain" xlink:to="lab_us-gaap_BusinessAcquisitionAcquireeDomain" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DrillformTechnicalServicesLtdMember" xlink:label="loc_hmh_DrillformTechnicalServicesLtdMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DrillformTechnicalServicesLtdMember" xml:lang="en-US">Drillform Technical Services Ltd [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DrillformTechnicalServicesLtdMember" xlink:to="lab_hmh_DrillformTechnicalServicesLtdMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DeepBlueOilGasLimitedMember" xlink:label="loc_hmh_DeepBlueOilGasLimitedMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DeepBlueOilGasLimitedMember" xml:lang="en-US">Deep Blue Oil &amp; Gas Limited [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_DeepBlueOilGasLimitedMember" xml:lang="en-US">Deep Blue</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DeepBlueOilGasLimitedMember" xlink:to="lab_hmh_DeepBlueOilGasLimitedMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DeepBlueOilGasLimitedMember" xml:lang="en-US">Deep Blue Oil &amp; Gas Limited</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CashAcquiredFromAcquisition" xlink:label="loc_us-gaap_CashAcquiredFromAcquisition" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CashAcquiredFromAcquisition" xml:lang="en-US">Cash Acquired from Acquisition</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CashAcquiredFromAcquisition" xml:lang="en-US">Cash acquired</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAcquiredFromAcquisition" xlink:to="lab_us-gaap_CashAcquiredFromAcquisition" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedAbstract" xlink:label="loc_hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedAbstract" xml:lang="en-US">Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedAbstract" xlink:to="lab_hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedAbstract" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTable" xlink:label="loc_hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTable" xml:lang="en-US">Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTable" xlink:to="lab_hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedLineItems" xlink:label="loc_hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedLineItems" xml:lang="en-US">Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedLineItems" xlink:to="lab_hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract" xml:lang="en-US">Business Combination, Recognized Asset Acquired, Asset [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract" xml:lang="en-US">Assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract" xlink:to="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetsAbstract" />
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsReceivables" xml:lang="en-US">Business Combination, Recognized Asset Acquired, Receivable, Current</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" xml:lang="en-US">Inventory</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" xlink:to="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedInventory" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" xml:lang="en-US">Business Combination, Recognized Asset Acquired, Prepaid Expense and Other Asset, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" xml:lang="en-US">Prepaid expenses and other current assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" xlink:to="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssetsPrepaidExpenseAndOtherAssets" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssets" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssets" xml:lang="en-US">Business Combination, Recognized Asset Acquired, Asset, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssets" xml:lang="en-US">Total current assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssets" xlink:to="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentAssets" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" xml:lang="en-US">Business Combination, Recognized Asset Acquired, Property, Plant, and Equipment</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" xml:lang="en-US">Property and equipment</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" xlink:to="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedPropertyPlantAndEquipment" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets" xml:lang="en-US">Business Combination, Recognized Asset Acquired, Asset</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets" xml:lang="en-US">Total assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets" xlink:to="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract" xml:lang="en-US">Business Combination, Recognized Liability Assumed, Liability [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract" xml:lang="en-US">Liabilities and equity</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract" xlink:to="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilitiesAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAbstract" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAbstract" xml:lang="en-US">Business Combination, Recognized Liability Assumed, Liability, Current [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAbstract" xml:lang="en-US">Current liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAbstract" xlink:to="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAbstract" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesCustomerDeposits" xlink:label="loc_hmh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesCustomerDeposits" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesCustomerDeposits" xml:lang="en-US">Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Customer Deposits</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesCustomerDeposits" xml:lang="en-US">Customer deposits</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesCustomerDeposits" xml:lang="en-US">Business combination recognized identifiable assets acquired and liabilities assumed current liabilities customer deposits.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable" xml:lang="en-US">Business Combination, Recognized Liability Assumed, Accounts Payable, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable" xml:lang="en-US">Accounts payable</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable" xlink:to="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesAccountsPayable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesWarrantyLiability" xlink:label="loc_hmh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesWarrantyLiability" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesWarrantyLiability" xml:lang="en-US">Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Warranty Liability</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesWarrantyLiability" xml:lang="en-US">Warranty liability</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesWarrantyLiability" xlink:to="lab_hmh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesWarrantyLiability" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesWarrantyLiability" xml:lang="en-US">Business combination recognized identifiable assets acquired and liabilities assumed current liabilities warranty liability.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities" xml:lang="en-US">Business Combination, Recognized Liability Assumed, Deferred Tax Liability</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDeferredTaxLiabilities" xml:lang="en-US">Deferred tax liability</link:label>
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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilities" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilities" xml:lang="en-US">Business Combination, Recognized Liability Assumed, Liability, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilities" xml:lang="en-US">Total current liabilities</link:label>
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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation" xml:lang="en-US">Business Combination, Recognized Liability Assumed, Lease Obligation</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCapitalLeaseObligation" xml:lang="en-US">Total debt and leases</link:label>
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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedContingentLiability" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedContingentLiability" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedContingentLiability" xml:lang="en-US">Business Combination, Recognized Liability Assumed, Contingent Liability</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedContingentLiability" xml:lang="en-US">Contingent consideration</link:label>
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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities" xml:lang="en-US">Business Combination, Recognized Liability Assumed, Liability</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedLiabilities" xml:lang="en-US">Total liabilities</link:label>
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          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet" xml:lang="en-US">Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet" xml:lang="en-US">Equity consideration</link:label>
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          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfFiniteLivedIntangibleAssetsAbstract" xlink:label="loc_hmh_ScheduleOfFiniteLivedIntangibleAssetsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfFiniteLivedIntangibleAssetsAbstract" xml:lang="en-US">Schedule Of Finite Lived Intangible Assets [Abstract]</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DevelopedTechnologyRightsMember" xml:lang="en-US">Developed Technology Rights [Member]</link:label>
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          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual" xml:lang="en-US">Business Combination, Acquiree's Earnings (Loss) since Acquisition Date, Actual</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual" xml:lang="en-US">Net income</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual" xlink:to="lab_us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionProFormaInformationAbstract" xlink:label="loc_us-gaap_BusinessAcquisitionProFormaInformationAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionProFormaInformationAbstract" xml:lang="en-US">Business Combination, Pro Forma Information [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionProFormaInformationAbstract" xlink:to="lab_us-gaap_BusinessAcquisitionProFormaInformationAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionProFormaInformationNonrecurringAdjustmentsTable" xlink:label="loc_us-gaap_BusinessAcquisitionProFormaInformationNonrecurringAdjustmentsTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionProFormaInformationNonrecurringAdjustmentsTable" xml:lang="en-US">Business Combination, Pro Forma Information [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionProFormaInformationNonrecurringAdjustmentsTable" xlink:to="lab_us-gaap_BusinessAcquisitionProFormaInformationNonrecurringAdjustmentsTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionProFormaInformationNonrecurringAdjustmentLineItems" xlink:label="loc_us-gaap_BusinessAcquisitionProFormaInformationNonrecurringAdjustmentLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionProFormaInformationNonrecurringAdjustmentLineItems" xml:lang="en-US">Business Combination, Pro Forma Information [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionProFormaInformationNonrecurringAdjustmentLineItems" xlink:to="lab_us-gaap_BusinessAcquisitionProFormaInformationNonrecurringAdjustmentLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionsProFormaRevenue" xlink:label="loc_us-gaap_BusinessAcquisitionsProFormaRevenue" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionsProFormaRevenue" xml:lang="en-US">Business Combination, Pro Forma Information, Pro Forma Revenue</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessAcquisitionsProFormaRevenue" xml:lang="en-US">Revenues</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionsProFormaRevenue" xlink:to="lab_us-gaap_BusinessAcquisitionsProFormaRevenue" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss" xlink:label="loc_us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss" xml:lang="en-US">Business Combination, Pro Forma Information, Pro Forma Income (Loss), after Tax</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss" xml:lang="en-US">Net income attributable</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss" xlink:to="lab_us-gaap_BusinessAcquisitionsProFormaNetIncomeLoss" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareBasic" xlink:label="loc_us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareBasic" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareBasic" xml:lang="en-US">Business Combination, Pro Forma Information, Pro Forma Income (Loss) from Continuing Operations, after Tax, Per Basic Share</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareBasic" xml:lang="en-US">Net income per common share&#8212;basic</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareBasic" xlink:to="lab_us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareBasic" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareDiluted" xlink:label="loc_us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareDiluted" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareDiluted" xml:lang="en-US">Business Combination, Pro Forma Information, Pro Forma Income (Loss) from Continuing Operations, after Tax, Per Diluted Share</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareDiluted" xml:lang="en-US">Net income per common share&#8212;diluted</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareDiluted" xlink:to="lab_us-gaap_BusinessAcquisitionProFormaIncomeLossFromContinuingOperationsBeforeChangesInAccountingAndExtraordinaryItemsNetOfTaxPerShareDiluted" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryValuationReserves" xlink:label="loc_us-gaap_InventoryValuationReserves" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InventoryValuationReserves" xml:lang="en-US">Inventory Valuation Reserves</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_InventoryValuationReserves" xml:lang="en-US">Inventories, net of reserves</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryValuationReserves" xlink:to="lab_us-gaap_InventoryValuationReserves" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ProvisionForInventoryWriteDown" xlink:label="loc_hmh_ProvisionForInventoryWriteDown" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ProvisionForInventoryWriteDown" xml:lang="en-US">Provision for Inventory Write Down</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ProvisionForInventoryWriteDown" xlink:to="lab_hmh_ProvisionForInventoryWriteDown" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ProvisionForInventoryWriteDown" xml:lang="en-US">Provision for inventory write-down.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryRawMaterialsNetOfReserves" xlink:label="loc_us-gaap_InventoryRawMaterialsNetOfReserves" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InventoryRawMaterialsNetOfReserves" xml:lang="en-US">Inventory, Raw Materials, Net of Reserves</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_InventoryRawMaterialsNetOfReserves" xml:lang="en-US">Stock of raw materials</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryRawMaterialsNetOfReserves" xlink:to="lab_us-gaap_InventoryRawMaterialsNetOfReserves" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryWorkInProcessNetOfReserves" xlink:label="loc_us-gaap_InventoryWorkInProcessNetOfReserves" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InventoryWorkInProcessNetOfReserves" xml:lang="en-US">Inventory, Work in Process, Net of Reserves</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_InventoryWorkInProcessNetOfReserves" xml:lang="en-US">Work in progress</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryWorkInProcessNetOfReserves" xlink:to="lab_us-gaap_InventoryWorkInProcessNetOfReserves" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InventoryFinishedGoodsNetOfReserves" xlink:label="loc_us-gaap_InventoryFinishedGoodsNetOfReserves" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InventoryFinishedGoodsNetOfReserves" xml:lang="en-US">Inventory, Finished Goods, Net of Reserves</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_InventoryFinishedGoodsNetOfReserves" xml:lang="en-US">Finished goods</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InventoryFinishedGoodsNetOfReserves" xlink:to="lab_us-gaap_InventoryFinishedGoodsNetOfReserves" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GoodwillAcquiredDuringPeriod" xlink:label="loc_us-gaap_GoodwillAcquiredDuringPeriod" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GoodwillAcquiredDuringPeriod" xml:lang="en-US">Goodwill, Acquired During Period</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_GoodwillAcquiredDuringPeriod" xml:lang="en-US">Acquisition and other</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillAcquiredDuringPeriod" xlink:to="lab_us-gaap_GoodwillAcquiredDuringPeriod" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GoodwillForeignCurrencyTranslationGainLoss" xlink:label="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GoodwillForeignCurrencyTranslationGainLoss" xml:lang="en-US">Goodwill, Foreign Currency Translation, Gain (Loss)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_GoodwillForeignCurrencyTranslationGainLoss" xml:lang="en-US">Currency translation differences</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss" xlink:to="lab_us-gaap_GoodwillForeignCurrencyTranslationGainLoss" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_GoodwillAcquisitionsAndMeasurementPeriodAdjustments" xlink:label="loc_hmh_GoodwillAcquisitionsAndMeasurementPeriodAdjustments" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_GoodwillAcquisitionsAndMeasurementPeriodAdjustments" xml:lang="en-US">Goodwill Acquisitions And Measurement Period Adjustments</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_hmh_GoodwillAcquisitionsAndMeasurementPeriodAdjustments" xml:lang="en-US">Acquisition and purchase accounting adjustments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_GoodwillAcquisitionsAndMeasurementPeriodAdjustments" xlink:to="lab_hmh_GoodwillAcquisitionsAndMeasurementPeriodAdjustments" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_GoodwillAcquisitionsAndMeasurementPeriodAdjustments" xml:lang="en-US">Goodwill acquisitions and measurement period adjustments.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StatementBusinessSegmentsAxis" xml:lang="en-US">Segments [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StatementBusinessSegmentsAxis" xml:lang="en-US">Segments [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis" xlink:to="lab_us-gaap_StatementBusinessSegmentsAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentDomain" xlink:label="loc_us-gaap_SegmentDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SegmentDomain" xml:lang="en-US">Segments [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SegmentDomain" xml:lang="en-US">Segments [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentDomain" xlink:to="lab_us-gaap_SegmentDomain" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ESSSegmentMember" xlink:label="loc_hmh_ESSSegmentMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ESSSegmentMember" xml:lang="en-US">ESS Segment [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ESSSegmentMember" xml:lang="en-US">ESS</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ESSSegmentMember" xlink:to="lab_hmh_ESSSegmentMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ESSSegmentMember" xml:lang="en-US">ESS Segment</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_PCSSegmentMember" xlink:label="loc_hmh_PCSSegmentMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_PCSSegmentMember" xml:lang="en-US">PCS Segment [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_PCSSegmentMember" xml:lang="en-US">PCS</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_PCSSegmentMember" xlink:to="lab_hmh_PCSSegmentMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_PCSSegmentMember" xml:lang="en-US">PCS Segment</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CostOfGoodsAndServicesSoldDepreciation" xlink:label="loc_us-gaap_CostOfGoodsAndServicesSoldDepreciation" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CostOfGoodsAndServicesSoldDepreciation" xml:lang="en-US">Cost, Depreciation</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_CostOfGoodsAndServicesSoldDepreciation" xml:lang="en-US">Depreciation expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CostOfGoodsAndServicesSoldDepreciation" xlink:to="lab_us-gaap_CostOfGoodsAndServicesSoldDepreciation" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PropertyPlantAndEquipmentGross" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentGross" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentGross" xml:lang="en-US">Property, Plant, and Equipment, before Accumulated Depreciation, Depletion, and Amortization</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_PropertyPlantAndEquipmentGross" xml:lang="en-US">Property plant and equipment gross</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentGross" xlink:to="lab_us-gaap_PropertyPlantAndEquipmentGross" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LandAndBuildingMember" xlink:label="loc_us-gaap_LandAndBuildingMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LandAndBuildingMember" xml:lang="en-US">Land and Building [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LandAndBuildingMember" xml:lang="en-US">Buildings and land [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LandAndBuildingMember" xlink:to="lab_us-gaap_LandAndBuildingMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetUnderConstructionMember" xlink:label="loc_us-gaap_AssetUnderConstructionMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AssetUnderConstructionMember" xml:lang="en-US">Asset under Construction [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetUnderConstructionMember" xlink:to="lab_us-gaap_AssetUnderConstructionMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable" xml:lang="en-US">Derivative Instruments and Hedging Activities Disclosures [Table]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable" xml:lang="en-US">Derivative Instruments and Hedging Activities Disclosures [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable" xlink:to="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationAxis" xlink:label="loc_us-gaap_HedgingDesignationAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_HedgingDesignationAxis" xml:lang="en-US">Hedging Designation [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_HedgingDesignationAxis" xml:lang="en-US">Hedging Designation [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_HedgingDesignationAxis" xlink:to="lab_us-gaap_HedgingDesignationAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_HedgingDesignationDomain" xlink:label="loc_us-gaap_HedgingDesignationDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_HedgingDesignationDomain" xml:lang="en-US">Hedging Designation [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_HedgingDesignationDomain" xml:lang="en-US">Hedging Designation [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_HedgingDesignationDomain" xlink:to="lab_us-gaap_HedgingDesignationDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NondesignatedMember" xlink:label="loc_us-gaap_NondesignatedMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NondesignatedMember" xml:lang="en-US">Not Designated as Hedging Instrument [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NondesignatedMember" xml:lang="en-US">Derivative financial instruments&#8212;not designated as hedging instruments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NondesignatedMember" xlink:to="lab_us-gaap_NondesignatedMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems" xlink:label="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems" xml:lang="en-US">Derivative Instruments and Hedging Activities Disclosures [Line Items]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems" xml:lang="en-US">Derivative Instruments and Hedging Activities Disclosures [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems" xlink:to="lab_us-gaap_DerivativeInstrumentsAndHedgingActivitiesDisclosuresLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeGainLossOnDerivativeNet" xlink:label="loc_us-gaap_DerivativeGainLossOnDerivativeNet" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativeGainLossOnDerivativeNet" xml:lang="en-US">Derivative, Gain (Loss) on Derivative, Net</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_DerivativeGainLossOnDerivativeNet" xml:lang="en-US">Loss related to non-designated hedges</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeGainLossOnDerivativeNet" xlink:to="lab_us-gaap_DerivativeGainLossOnDerivativeNet" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DesignatedAsHedgingInstrumentMember" xlink:label="loc_us-gaap_DesignatedAsHedgingInstrumentMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DesignatedAsHedgingInstrumentMember" xml:lang="en-US">Designated as Hedging Instrument [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DesignatedAsHedgingInstrumentMember" xml:lang="en-US">Derivative financial instruments&#8212;designated as cash flow hedging instruments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DesignatedAsHedgingInstrumentMember" xlink:to="lab_us-gaap_DesignatedAsHedgingInstrumentMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis" xml:lang="en-US">Fair Value Hierarchy and NAV [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis" xml:lang="en-US">Fair Value Hierarchy and NAV [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:to="lab_us-gaap_FairValueByFairValueHierarchyLevelAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:label="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xml:lang="en-US">Fair Value Hierarchy and NAV [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xml:lang="en-US">Fair Value Hierarchy and NAV [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" xlink:to="lab_us-gaap_FairValueMeasurementsFairValueHierarchyDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="loc_us-gaap_FairValueInputsLevel1Member" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueInputsLevel1Member" xml:lang="en-US">Fair Value, Inputs, Level 1 [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FairValueInputsLevel1Member" xml:lang="en-US">Level 1</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueInputsLevel1Member" xlink:to="lab_us-gaap_FairValueInputsLevel1Member" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="loc_us-gaap_FairValueInputsLevel2Member" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueInputsLevel2Member" xml:lang="en-US">Fair Value, Inputs, Level 2 [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FairValueInputsLevel2Member" xml:lang="en-US">Level 2</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueInputsLevel2Member" xlink:to="lab_us-gaap_FairValueInputsLevel2Member" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FairValueInputsLevel3Member" xlink:label="loc_us-gaap_FairValueInputsLevel3Member" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FairValueInputsLevel3Member" xml:lang="en-US">Fair Value, Inputs, Level 3 [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FairValueInputsLevel3Member" xml:lang="en-US">Level 3</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueInputsLevel3Member" xlink:to="lab_us-gaap_FairValueInputsLevel3Member" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAssets" xlink:label="loc_us-gaap_DerivativeAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativeAssets" xml:lang="en-US">Derivative Asset</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DerivativeAssets" xml:lang="en-US">Derivative financial instruments, Assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeAssets" xlink:to="lab_us-gaap_DerivativeAssets" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AssetsFairValueDisclosure" xlink:label="loc_us-gaap_AssetsFairValueDisclosure" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AssetsFairValueDisclosure" xml:lang="en-US">Assets, Fair Value Disclosure</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_AssetsFairValueDisclosure" xml:lang="en-US">Total assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsFairValueDisclosure" xlink:to="lab_us-gaap_AssetsFairValueDisclosure" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilities" xlink:label="loc_us-gaap_DerivativeLiabilities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativeLiabilities" xml:lang="en-US">Derivative Liability</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DerivativeLiabilities" xml:lang="en-US">Derivative financial instruments, Liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeLiabilities" xlink:to="lab_us-gaap_DerivativeLiabilities" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LiabilitiesFairValueDisclosure" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LiabilitiesFairValueDisclosure" xml:lang="en-US">Liabilities, Fair Value Disclosure</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_LiabilitiesFairValueDisclosure" xml:lang="en-US">Total liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosure" xlink:to="lab_us-gaap_LiabilitiesFairValueDisclosure" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeInstrumentRiskAxis" xlink:label="loc_us-gaap_DerivativeInstrumentRiskAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativeInstrumentRiskAxis" xml:lang="en-US">Derivative Instrument [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DerivativeInstrumentRiskAxis" xml:lang="en-US">Derivative Instrument [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeInstrumentRiskAxis" xlink:to="lab_us-gaap_DerivativeInstrumentRiskAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeContractTypeDomain" xlink:label="loc_us-gaap_DerivativeContractTypeDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativeContractTypeDomain" xml:lang="en-US">Derivative Contract [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DerivativeContractTypeDomain" xml:lang="en-US">Derivative Contract [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeContractTypeDomain" xlink:to="lab_us-gaap_DerivativeContractTypeDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignExchangeForwardMember" xlink:label="loc_us-gaap_ForeignExchangeForwardMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ForeignExchangeForwardMember" xml:lang="en-US">Foreign Exchange Forward [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ForeignExchangeForwardMember" xml:lang="en-US">Foreign exchange forward contracts</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ForeignExchangeForwardMember" xlink:to="lab_us-gaap_ForeignExchangeForwardMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_HedgingPurposeAxis" xlink:label="loc_hmh_HedgingPurposeAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_HedgingPurposeAxis" xml:lang="en-US">Hedging Purpose [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_HedgingPurposeAxis" xml:lang="en-US">Hedging Purpose [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_HedgingPurposeAxis" xlink:to="lab_hmh_HedgingPurposeAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_HedgingPurposeAxis" xml:lang="en-US">Hedging Purpose</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_HedgingPurposeDomain" xlink:label="loc_hmh_HedgingPurposeDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_HedgingPurposeDomain" xml:lang="en-US">Hedging Purpose [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_HedgingPurposeDomain" xml:lang="en-US">Hedging Purpose [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_HedgingPurposeDomain" xlink:to="lab_hmh_HedgingPurposeDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_HedgingPurposeDomain" xml:lang="en-US">Hedging Purpose [Domain]</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ForecastedSalesMember" xlink:label="loc_hmh_ForecastedSalesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ForecastedSalesMember" xml:lang="en-US">Forecasted Sales [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ForecastedSalesMember" xml:lang="en-US">Foreign exchange forward contracts to hedge highly probable forecasted sales:</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ForecastedSalesMember" xlink:to="lab_hmh_ForecastedSalesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ForecastedSalesMember" xml:lang="en-US">Forecasted Sales</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ForecastedPurchasesMember" xlink:label="loc_hmh_ForecastedPurchasesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ForecastedPurchasesMember" xml:lang="en-US">Forecasted Purchases [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ForecastedPurchasesMember" xml:lang="en-US">Foreign exchange forward contracts to hedge highly probable forecasted purchases:</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ForecastedPurchasesMember" xlink:to="lab_hmh_ForecastedPurchasesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ForecastedPurchasesMember" xml:lang="en-US">Forecasted Purchases</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ForecastedPurchasesOneMember" xlink:label="loc_hmh_ForecastedPurchasesOneMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ForecastedPurchasesOneMember" xml:lang="en-US">Forecasted Purchases One [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ForecastedPurchasesOneMember" xml:lang="en-US">Foreign exchange forward contracts to hedge highly probable forecasted purchases:</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ForecastedPurchasesOneMember" xlink:to="lab_hmh_ForecastedPurchasesOneMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DerivativeMaturityAxis" xlink:label="loc_hmh_DerivativeMaturityAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DerivativeMaturityAxis" xml:lang="en-US">Derivative Maturity [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_DerivativeMaturityAxis" xml:lang="en-US">Derivative Maturity [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DerivativeMaturityAxis" xlink:to="lab_hmh_DerivativeMaturityAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DerivativeMaturityAxis" xml:lang="en-US">Derivative Maturity</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DerivativeMaturityDomain" xlink:label="loc_hmh_DerivativeMaturityDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DerivativeMaturityDomain" xml:lang="en-US">Derivative Maturity [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_DerivativeMaturityDomain" xml:lang="en-US">Derivative Maturity [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DerivativeMaturityDomain" xlink:to="lab_hmh_DerivativeMaturityDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DerivativeMaturityDomain" xml:lang="en-US">Derivative Maturity [Domain]</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_SixMonthsOrLessMember" xlink:label="loc_hmh_SixMonthsOrLessMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_SixMonthsOrLessMember" xml:lang="en-US">Six Months Or Less [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_SixMonthsOrLessMember" xml:lang="en-US">6 months and less</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_SixMonthsOrLessMember" xlink:to="lab_hmh_SixMonthsOrLessMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_SixMonthsOrLessMember" xml:lang="en-US">Six Months Or Less</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_SixToTwelveMonthsMember" xlink:label="loc_hmh_SixToTwelveMonthsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_SixToTwelveMonthsMember" xml:lang="en-US">Six To Twelve Months [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_SixToTwelveMonthsMember" xml:lang="en-US">6-12 months</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_SixToTwelveMonthsMember" xlink:to="lab_hmh_SixToTwelveMonthsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_SixToTwelveMonthsMember" xml:lang="en-US">Six To Twelve Months</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OneToTwoYearsMember" xlink:label="loc_hmh_OneToTwoYearsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OneToTwoYearsMember" xml:lang="en-US">One To Two Years [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_OneToTwoYearsMember" xml:lang="en-US">1-2 years</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OneToTwoYearsMember" xlink:to="lab_hmh_OneToTwoYearsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_OneToTwoYearsMember" xml:lang="en-US">One To Two Years</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeNotionalAmount" xlink:label="loc_us-gaap_DerivativeNotionalAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativeNotionalAmount" xml:lang="en-US">Derivative, Notional Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DerivativeNotionalAmount" xml:lang="en-US">Notional amounts</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeNotionalAmount" xlink:to="lab_us-gaap_DerivativeNotionalAmount" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeAverageForwardExchangeRate1" xlink:label="loc_us-gaap_DerivativeAverageForwardExchangeRate1" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativeAverageForwardExchangeRate1" xml:lang="en-US">Derivative, Average Forward Exchange Rate</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DerivativeAverageForwardExchangeRate1" xml:lang="en-US">Average forward rate</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeAverageForwardExchangeRate1" xlink:to="lab_us-gaap_DerivativeAverageForwardExchangeRate1" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_HedgingReserve" xlink:label="loc_hmh_HedgingReserve" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_HedgingReserve" xml:lang="en-US">Hedging Reserve</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_hmh_HedgingReserve" xml:lang="en-US">Beginning balance</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_hmh_HedgingReserve" xml:lang="en-US">Ending balance</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_HedgingReserve" xlink:to="lab_hmh_HedgingReserve" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_HedgingReserve" xml:lang="en-US">Hedging reserve.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossBeforeReclassificationAndTax" xlink:label="loc_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossBeforeReclassificationAndTax" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossBeforeReclassificationAndTax" xml:lang="en-US">Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss), before Reclassification and Tax</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossBeforeReclassificationAndTax" xml:lang="en-US">Change in foreign currency risk</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossBeforeReclassificationAndTax" xlink:to="lab_us-gaap_OtherComprehensiveIncomeForeignCurrencyTransactionAndTranslationGainLossBeforeReclassificationAndTax" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterTax" xlink:label="loc_hmh_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterTax" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterTax" xml:lang="en-US">Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Tax</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterTax" xml:lang="en-US">Income tax allocated to cash flow hedges</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterTax" xlink:to="lab_hmh_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterTax" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterTax" xml:lang="en-US">Other comprehensive income loss cash flow hedge gain loss after tax.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TaxesPayableCurrent" xlink:label="loc_us-gaap_TaxesPayableCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TaxesPayableCurrent" xml:lang="en-US">Taxes Payable, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_TaxesPayableCurrent" xml:lang="en-US">Income tax payable</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TaxesPayableCurrent" xlink:to="lab_us-gaap_TaxesPayableCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityCurrent" xlink:label="loc_us-gaap_OperatingLeaseLiabilityCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingLeaseLiabilityCurrent" xml:lang="en-US">Operating Lease, Liability, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_OperatingLeaseLiabilityCurrent" xml:lang="en-US">Operating lease liability</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OperatingLeaseLiabilityCurrent" xml:lang="en-US">Current operating lease liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeaseLiabilityCurrent" xlink:to="lab_us-gaap_OperatingLeaseLiabilityCurrent" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_PublicDutiesAndTaxesPayableCurrent" xlink:label="loc_hmh_PublicDutiesAndTaxesPayableCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_PublicDutiesAndTaxesPayableCurrent" xml:lang="en-US">Public Duties and Taxes Payable, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_PublicDutiesAndTaxesPayableCurrent" xml:lang="en-US">Public duties and taxes</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_PublicDutiesAndTaxesPayableCurrent" xlink:to="lab_hmh_PublicDutiesAndTaxesPayableCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_PublicDutiesAndTaxesPayableCurrent" xml:lang="en-US">Public Duties and Taxes Payable, Current</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DerivativeLiabilitiesCurrent" xlink:label="loc_us-gaap_DerivativeLiabilitiesCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DerivativeLiabilitiesCurrent" xml:lang="en-US">Derivative Liability, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DerivativeLiabilitiesCurrent" xml:lang="en-US">External derivative financial liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativeLiabilitiesCurrent" xlink:to="lab_us-gaap_DerivativeLiabilitiesCurrent" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_WithheldTaxesAndOtherDeductionsCurrent" xlink:label="loc_hmh_WithheldTaxesAndOtherDeductionsCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_WithheldTaxesAndOtherDeductionsCurrent" xml:lang="en-US">Withheld Taxes and Other Deductions, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_WithheldTaxesAndOtherDeductionsCurrent" xml:lang="en-US">Withheld taxes and other deductions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_WithheldTaxesAndOtherDeductionsCurrent" xlink:to="lab_hmh_WithheldTaxesAndOtherDeductionsCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_WithheldTaxesAndOtherDeductionsCurrent" xml:lang="en-US">Withheld Taxes and Other Deductions, Current</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherSundryLiabilitiesCurrent" xlink:label="loc_us-gaap_OtherSundryLiabilitiesCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherSundryLiabilitiesCurrent" xml:lang="en-US">Other Sundry Liabilities, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherSundryLiabilitiesCurrent" xml:lang="en-US">Other</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherSundryLiabilitiesCurrent" xlink:to="lab_us-gaap_OtherSundryLiabilitiesCurrent" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DeferredAndContingentLiabilitiesCurrent" xlink:label="loc_hmh_DeferredAndContingentLiabilitiesCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DeferredAndContingentLiabilitiesCurrent" xml:lang="en-US">Deferred and Contingent Liabilities Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_DeferredAndContingentLiabilitiesCurrent" xml:lang="en-US">Short-term deferred and contingent liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DeferredAndContingentLiabilitiesCurrent" xlink:to="lab_hmh_DeferredAndContingentLiabilitiesCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DeferredAndContingentLiabilitiesCurrent" xml:lang="en-US">Deferred and Contingent Liabilities Current</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AmortizationOfIntangibleAssets" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AmortizationOfIntangibleAssets" xml:lang="en-US">Intangible Asset, Finite-Lived, Amortization Expense</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_AmortizationOfIntangibleAssets" xml:lang="en-US">Amortization expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AmortizationOfIntangibleAssets" xlink:to="lab_us-gaap_AmortizationOfIntangibleAssets" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetUsefulLife" xml:lang="en-US">Intangible Asset, Finite-Lived, Useful Life</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetUsefulLife" xml:lang="en-US">Useful&#160;life</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetUsefulLife" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsGross" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsGross" xml:lang="en-US">Intangible Asset, Finite-Lived, before Accumulated Amortization</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsGross" xml:lang="en-US">Gross carrying amount</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsGross" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsGross" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PatentsMember" xlink:label="loc_us-gaap_PatentsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PatentsMember" xml:lang="en-US">Patents [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_PatentsMember" xml:lang="en-US">Patents and rights [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PatentsMember" xlink:to="lab_us-gaap_PatentsMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DevelopmentCostsMember" xlink:label="loc_hmh_DevelopmentCostsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DevelopmentCostsMember" xml:lang="en-US">Development Costs [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DevelopmentCostsMember" xlink:to="lab_hmh_DevelopmentCostsMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract" xml:lang="en-US">Intangible Asset, Finite-Lived, after Accumulated Amortization, Estimated Amortization Expense, Fiscal Year Maturity [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsFutureAmortizationExpenseAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" xml:lang="en-US">Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year One</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" xml:lang="en-US">2026</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xml:lang="en-US">Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Two</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xml:lang="en-US">2027</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree" xml:lang="en-US">Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Three</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree" xml:lang="en-US">2028</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearThree" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour" xml:lang="en-US">Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Four</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour" xml:lang="en-US">2029</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive" xml:lang="en-US">Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Five</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive" xml:lang="en-US">2030</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFive" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive" xml:lang="en-US">Intangible Asset, Finite-Lived, Estimated Amortization Expense, after Year Five</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive" xml:lang="en-US">Thereafter</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive" xlink:to="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseAfterYearFive" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseCost" xlink:label="loc_us-gaap_OperatingLeaseCost" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingLeaseCost" xml:lang="en-US">Operating Lease, Cost</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OperatingLeaseCost" xml:lang="en-US">Operating lease cost</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeaseCost" xlink:to="lab_us-gaap_OperatingLeaseCost" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiability" xlink:label="loc_us-gaap_OperatingLeaseLiability" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingLeaseLiability" xml:lang="en-US">Operating Lease, Liability</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_OperatingLeaseLiability" xml:lang="en-US">Operating Lease, Liability</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_OperatingLeaseLiability" xml:lang="en-US">Present value of lease liabilities</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OperatingLeaseLiability" xml:lang="en-US">Present value of lease liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeaseLiability" xlink:to="lab_us-gaap_OperatingLeaseLiability" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_LeaseTypeAxis" xlink:label="loc_hmh_LeaseTypeAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_LeaseTypeAxis" xml:lang="en-US">Lease Type [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_LeaseTypeAxis" xlink:to="lab_hmh_LeaseTypeAxis" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_LeaseTypeDomain" xlink:label="loc_hmh_LeaseTypeDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_LeaseTypeDomain" xml:lang="en-US">Lease Type [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_LeaseTypeDomain" xlink:to="lab_hmh_LeaseTypeDomain" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_KristiansandLeaseMember" xlink:label="loc_hmh_KristiansandLeaseMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_KristiansandLeaseMember" xml:lang="en-US">Kristiansand Lease [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_KristiansandLeaseMember" xlink:to="lab_hmh_KristiansandLeaseMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilityAbstract" xlink:label="loc_us-gaap_OperatingLeaseLiabilityAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingLeaseLiabilityAbstract" xml:lang="en-US">Operating Lease, Liability [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeaseLiabilityAbstract" xlink:to="lab_us-gaap_OperatingLeaseLiabilityAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LeaseCostAbstract" xlink:label="loc_us-gaap_LeaseCostAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LeaseCostAbstract" xml:lang="en-US">Lease, Cost [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LeaseCostAbstract" xlink:to="lab_us-gaap_LeaseCostAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SubleaseIncome" xlink:label="loc_us-gaap_SubleaseIncome" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SubleaseIncome" xml:lang="en-US">Sublease Income</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SubleaseIncome" xml:lang="en-US">Sublease income</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubleaseIncome" xlink:to="lab_us-gaap_SubleaseIncome" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LeaseCost" xlink:label="loc_us-gaap_LeaseCost" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LeaseCost" xml:lang="en-US">Lease, Cost</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_LeaseCost" xml:lang="en-US">Net lease cost</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LeaseCost" xlink:to="lab_us-gaap_LeaseCost" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract" xlink:label="loc_us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract" xml:lang="en-US">Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract" xlink:to="lab_us-gaap_OperatingLeaseLiabilitiesPaymentsDueAbstract" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_LesseeOperatingLeaseLiabilityMaturityTable" xlink:label="loc_hmh_LesseeOperatingLeaseLiabilityMaturityTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_LesseeOperatingLeaseLiabilityMaturityTable" xml:lang="en-US">Lessee Operating Lease Liability Maturity [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_LesseeOperatingLeaseLiabilityMaturityTable" xlink:to="lab_hmh_LesseeOperatingLeaseLiabilityMaturityTable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_LesseeOperatingLeaseLiabilityMaturityLineItems" xlink:label="loc_hmh_LesseeOperatingLeaseLiabilityMaturityLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_LesseeOperatingLeaseLiabilityMaturityLineItems" xml:lang="en-US">Lessee Operating Lease Liability Maturity [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_LesseeOperatingLeaseLiabilityMaturityLineItems" xlink:to="lab_hmh_LesseeOperatingLeaseLiabilityMaturityLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" xml:lang="en-US">Lessee, Operating Lease, Liability, to be Paid, Year One</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" xml:lang="en-US">2026</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" xlink:to="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" xml:lang="en-US">Lessee, Operating Lease, Liability, to be Paid, Year Two</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" xml:lang="en-US">2027</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" xlink:to="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" xml:lang="en-US">Lessee, Operating Lease, Liability, to be Paid, Year Three</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" xml:lang="en-US">2028</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" xlink:to="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xml:lang="en-US">Lessee, Operating Lease, Liability, to be Paid, Year Four</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xml:lang="en-US">2029</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" xlink:to="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive" xml:lang="en-US">Lessee, Operating Lease, Liability, to be Paid, Year Five</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive" xml:lang="en-US">2030</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive" xlink:to="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive" xml:lang="en-US">Lessee, Operating Lease, Liability, to be Paid, after Year Five</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive" xml:lang="en-US">Thereafter</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive" xlink:to="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xml:lang="en-US">Lessee, Operating Lease, Liability, to be Paid</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xml:lang="en-US">Total lease payments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" xlink:to="lab_us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" xlink:label="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" xml:lang="en-US">Lessee, Operating Lease, Liability, Undiscounted Excess Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" xml:lang="en-US">Less: present value discount</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" xlink:to="lab_us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LesseeDisclosureAbstract" xlink:label="loc_us-gaap_LesseeDisclosureAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LesseeDisclosureAbstract" xml:lang="en-US">Lessee Disclosure [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LesseeDisclosureAbstract" xlink:to="lab_us-gaap_LesseeDisclosureAbstract" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_WeightedAverageRemainingTermAndWeightedAverageDiscountRatesTable" xlink:label="loc_hmh_WeightedAverageRemainingTermAndWeightedAverageDiscountRatesTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_WeightedAverageRemainingTermAndWeightedAverageDiscountRatesTable" xml:lang="en-US">Weighted Average Remaining Term and Weighted Average Discount Rates [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_WeightedAverageRemainingTermAndWeightedAverageDiscountRatesTable" xlink:to="lab_hmh_WeightedAverageRemainingTermAndWeightedAverageDiscountRatesTable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_WeightedAverageRemainingTermAndWeightedAverageDiscountRatesLineItems" xlink:label="loc_hmh_WeightedAverageRemainingTermAndWeightedAverageDiscountRatesLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_WeightedAverageRemainingTermAndWeightedAverageDiscountRatesLineItems" xml:lang="en-US">Weighted Average Remaining Term and Weighted Average Discount Rates [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_WeightedAverageRemainingTermAndWeightedAverageDiscountRatesLineItems" xlink:to="lab_hmh_WeightedAverageRemainingTermAndWeightedAverageDiscountRatesLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1" xlink:label="loc_us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1" xml:lang="en-US">Operating Lease, Weighted Average Remaining Lease Term</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1" xml:lang="en-US">Weighted-average remaining lease term (years)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1" xlink:to="lab_us-gaap_OperatingLeaseWeightedAverageRemainingLeaseTerm1" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" xlink:label="loc_us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" xml:lang="en-US">Operating Lease, Weighted Average Discount Rate, Percent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" xml:lang="en-US">Weighted-average discount rate</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" xlink:to="lab_us-gaap_OperatingLeaseWeightedAverageDiscountRatePercent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="loc_us-gaap_LongtermDebtTypeAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LongtermDebtTypeAxis" xml:lang="en-US">Long-Term Debt, Type [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LongtermDebtTypeAxis" xml:lang="en-US">Long-Term Debt, Type [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongtermDebtTypeAxis" xlink:to="lab_us-gaap_LongtermDebtTypeAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongtermDebtTypeDomain" xlink:label="loc_us-gaap_LongtermDebtTypeDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LongtermDebtTypeDomain" xml:lang="en-US">Long-Term Debt, Type [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LongtermDebtTypeDomain" xml:lang="en-US">Long-Term Debt, Type [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongtermDebtTypeDomain" xlink:to="lab_us-gaap_LongtermDebtTypeDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SeniorNotesMember" xlink:label="loc_us-gaap_SeniorNotesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SeniorNotesMember" xml:lang="en-US">Senior Notes [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SeniorNotesMember" xml:lang="en-US">7.875% Senior Secured Bonds due 2028</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SeniorNotesMember" xlink:to="lab_us-gaap_SeniorNotesMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_SevenPointEightSevenFiveSeniorSecuredBondsDue2028Member" xlink:label="loc_hmh_SevenPointEightSevenFiveSeniorSecuredBondsDue2028Member" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_SevenPointEightSevenFiveSeniorSecuredBondsDue2028Member" xml:lang="en-US">Seven Point Eight Seven Five Senior Secured Bonds due 2028 [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_SevenPointEightSevenFiveSeniorSecuredBondsDue2028Member" xlink:to="lab_hmh_SevenPointEightSevenFiveSeniorSecuredBondsDue2028Member" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_NinePointEightSevenFiveSeniorSecuredBondsDue2026Member" xlink:label="loc_hmh_NinePointEightSevenFiveSeniorSecuredBondsDue2026Member" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_NinePointEightSevenFiveSeniorSecuredBondsDue2026Member" xml:lang="en-US">Nine Point Eight Seven Five Senior Secured Bonds due 2026 [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_NinePointEightSevenFiveSeniorSecuredBondsDue2026Member" xlink:to="lab_hmh_NinePointEightSevenFiveSeniorSecuredBondsDue2026Member" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LoansPayableMember" xlink:label="loc_us-gaap_LoansPayableMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LoansPayableMember" xml:lang="en-US">Loans Payable [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LoansPayableMember" xlink:to="lab_us-gaap_LoansPayableMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ShareholderLoansMember" xlink:label="loc_hmh_ShareholderLoansMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ShareholderLoansMember" xml:lang="en-US">Shareholder Loans [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ShareholderLoansMember" xml:lang="en-US">Shareholder Loans</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ShareholderLoansMember" xlink:to="lab_hmh_ShareholderLoansMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ShareholderLoansMember" xml:lang="en-US">Shareholder Loans</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditMember" xlink:label="loc_us-gaap_LineOfCreditMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LineOfCreditMember" xml:lang="en-US">Line of Credit [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LineOfCreditMember" xml:lang="en-US">Line of Credit</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LineOfCreditMember" xlink:to="lab_us-gaap_LineOfCreditMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ForeignLineOfCreditMember" xlink:label="loc_us-gaap_ForeignLineOfCreditMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ForeignLineOfCreditMember" xml:lang="en-US">Foreign Line of Credit [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ForeignLineOfCreditMember" xml:lang="en-US">Credit Line in China</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ForeignLineOfCreditMember" xlink:to="lab_us-gaap_ForeignLineOfCreditMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtFairValue" xlink:label="loc_us-gaap_LongTermDebtFairValue" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LongTermDebtFairValue" xml:lang="en-US">Long-Term Debt, Fair Value</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LongTermDebtFairValue" xml:lang="en-US">Long-term debt, fair value</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_LongTermDebtFairValue" xml:lang="en-US">Long-Term Debt, Fair Value</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtFairValue" xlink:to="lab_us-gaap_LongTermDebtFairValue" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtInstrumentInterestRateStatedPercentage" xml:lang="en-US">Debt Instrument, Interest Rate, Stated Percentage</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DebtInstrumentInterestRateStatedPercentage" xml:lang="en-US">Stated interest rate</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:to="lab_us-gaap_DebtInstrumentInterestRateStatedPercentage" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentFaceAmount" xlink:label="loc_us-gaap_DebtInstrumentFaceAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtInstrumentFaceAmount" xml:lang="en-US">Debt Instrument, Face Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DebtInstrumentFaceAmount" xml:lang="en-US">Debt Instrument, Face Amount</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentFaceAmount" xlink:to="lab_us-gaap_DebtInstrumentFaceAmount" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentMaturityDate" xlink:label="loc_us-gaap_DebtInstrumentMaturityDate" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtInstrumentMaturityDate" xml:lang="en-US">Debt Instrument, Maturity Date</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DebtInstrumentMaturityDate" xml:lang="en-US">Debt Instrument, Maturity Date</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentMaturityDate" xlink:to="lab_us-gaap_DebtInstrumentMaturityDate" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AdditionalBondIssuanceCapacityAmount" xlink:label="loc_hmh_AdditionalBondIssuanceCapacityAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AdditionalBondIssuanceCapacityAmount" xml:lang="en-US">Additional Bond Issuance Capacity Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_AdditionalBondIssuanceCapacityAmount" xml:lang="en-US">Additional Bond Issuance Capacity Amount</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AdditionalBondIssuanceCapacityAmount" xlink:to="lab_hmh_AdditionalBondIssuanceCapacityAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AdditionalBondIssuanceCapacityAmount" xml:lang="en-US">Additional Bond Issuance Capacity Amount</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RatioOfIndebtednessToNetCapital1" xlink:label="loc_us-gaap_RatioOfIndebtednessToNetCapital1" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RatioOfIndebtednessToNetCapital1" xml:lang="en-US">Ratio of Indebtedness to Net Capital</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RatioOfIndebtednessToNetCapital1" xml:lang="en-US">Ratio of Indebtedness to Net Capital</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RatioOfIndebtednessToNetCapital1" xlink:to="lab_us-gaap_RatioOfIndebtednessToNetCapital1" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_InterestCoverageRatio" xlink:label="loc_hmh_InterestCoverageRatio" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_InterestCoverageRatio" xml:lang="en-US">Interest Coverage Ratio</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_InterestCoverageRatio" xml:lang="en-US">Interest Coverage Ratio</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_InterestCoverageRatio" xlink:to="lab_hmh_InterestCoverageRatio" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_InterestCoverageRatio" xml:lang="en-US">Interest Coverage Ratio</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_MinimumLiquidityRequiredUnderDebtAgreementAmount" xlink:label="loc_hmh_MinimumLiquidityRequiredUnderDebtAgreementAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_MinimumLiquidityRequiredUnderDebtAgreementAmount" xml:lang="en-US">Minimum Liquidity Required Under Debt Agreement Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_MinimumLiquidityRequiredUnderDebtAgreementAmount" xml:lang="en-US">Minimum Liquidity Required Under Debt Agreement Amount</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_MinimumLiquidityRequiredUnderDebtAgreementAmount" xlink:to="lab_hmh_MinimumLiquidityRequiredUnderDebtAgreementAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_MinimumLiquidityRequiredUnderDebtAgreementAmount" xml:lang="en-US">Minimum Liquidity Required Under Debt Agreement Amount</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRedemptionPricePercentage" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPricePercentage" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtInstrumentRedemptionPricePercentage" xml:lang="en-US">Debt Instrument, Redemption Price, Percentage</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DebtInstrumentRedemptionPricePercentage" xml:lang="en-US">Debt Instrument, Redemption Price, Percentage</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPricePercentage" xlink:to="lab_us-gaap_DebtInstrumentRedemptionPricePercentage" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DebtInstrumentMandatoryPrepaymentPricePercentage" xlink:label="loc_hmh_DebtInstrumentMandatoryPrepaymentPricePercentage" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DebtInstrumentMandatoryPrepaymentPricePercentage" xml:lang="en-US">Debt Instrument Mandatory Prepayment Price Percentage</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_DebtInstrumentMandatoryPrepaymentPricePercentage" xml:lang="en-US">Debt Instrument Mandatory Prepayment Price Percentage</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DebtInstrumentMandatoryPrepaymentPricePercentage" xlink:to="lab_hmh_DebtInstrumentMandatoryPrepaymentPricePercentage" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DebtInstrumentMandatoryPrepaymentPricePercentage" xml:lang="en-US">Debt Instrument Mandatory Prepayment Price Percentage</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentCarryingAmount" xlink:label="loc_us-gaap_DebtInstrumentCarryingAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtInstrumentCarryingAmount" xml:lang="en-US">Long-Term Debt, Gross</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DebtInstrumentCarryingAmount" xml:lang="en-US">Long-Term Debt, Gross</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentCarryingAmount" xlink:to="lab_us-gaap_DebtInstrumentCarryingAmount" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:label="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GainsLossesOnExtinguishmentOfDebt" xml:lang="en-US">Gain (Loss) on Extinguishment of Debt</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_GainsLossesOnExtinguishmentOfDebt" xml:lang="en-US">Gain (Loss) on Extinguishment of Debt</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GainsLossesOnExtinguishmentOfDebt" xlink:to="lab_us-gaap_GainsLossesOnExtinguishmentOfDebt" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DeferredTaxAssetConsiderationPayableAmount" xlink:label="loc_hmh_DeferredTaxAssetConsiderationPayableAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DeferredTaxAssetConsiderationPayableAmount" xml:lang="en-US">Deferred Tax Asset Consideration Payable Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_DeferredTaxAssetConsiderationPayableAmount" xml:lang="en-US">Deferred Tax Asset Consideration Payable Amount</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DeferredTaxAssetConsiderationPayableAmount" xlink:to="lab_hmh_DeferredTaxAssetConsiderationPayableAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DeferredTaxAssetConsiderationPayableAmount" xml:lang="en-US">Deferred Tax Asset Consideration Payable Amount</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredFinanceCostsNet" xlink:label="loc_us-gaap_DeferredFinanceCostsNet" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredFinanceCostsNet" xml:lang="en-US">Debt Issuance Costs, Net</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredFinanceCostsNet" xml:lang="en-US">Debt Issuance Costs, Net</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredFinanceCostsNet" xlink:to="lab_us-gaap_DeferredFinanceCostsNet" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:label="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xml:lang="en-US">Debt Instrument, Basis Spread on Variable Rate</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xml:lang="en-US">Debt Instrument, Basis Spread on Variable Rate</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" xlink:to="lab_us-gaap_DebtInstrumentBasisSpreadOnVariableRate1" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentUnusedBorrowingCapacityDescription" xlink:label="loc_us-gaap_DebtInstrumentUnusedBorrowingCapacityDescription" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtInstrumentUnusedBorrowingCapacityDescription" xml:lang="en-US">Debt Instrument, Unused Borrowing Capacity, Description</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DebtInstrumentUnusedBorrowingCapacityDescription" xml:lang="en-US">Debt Instrument, Unused Borrowing Capacity, Description</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentUnusedBorrowingCapacityDescription" xlink:to="lab_us-gaap_DebtInstrumentUnusedBorrowingCapacityDescription" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentUnusedBorrowingCapacityFee" xlink:label="loc_us-gaap_DebtInstrumentUnusedBorrowingCapacityFee" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtInstrumentUnusedBorrowingCapacityFee" xml:lang="en-US">Debt Instrument, Unused Borrowing Capacity, Fee</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DebtInstrumentUnusedBorrowingCapacityFee" xml:lang="en-US">Debt Instrument, Unused Borrowing Capacity, Fee</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentUnusedBorrowingCapacityFee" xlink:to="lab_us-gaap_DebtInstrumentUnusedBorrowingCapacityFee" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DebtInstrumentFairValuePercentageOfPrincipal" xlink:label="loc_hmh_DebtInstrumentFairValuePercentageOfPrincipal" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DebtInstrumentFairValuePercentageOfPrincipal" xml:lang="en-US">Debt Instrument Fair Value Percentage Of Principal</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_DebtInstrumentFairValuePercentageOfPrincipal" xml:lang="en-US">Debt Instrument Fair Value Percentage Of Principal</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DebtInstrumentFairValuePercentageOfPrincipal" xlink:to="lab_hmh_DebtInstrumentFairValuePercentageOfPrincipal" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DebtInstrumentFairValuePercentageOfPrincipal" xml:lang="en-US">Debt Instrument Fair Value Percentage Of Principal</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRedemptionPeriodAxis" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtInstrumentRedemptionPeriodAxis" xml:lang="en-US">Debt Instrument, Redemption, Period [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodAxis" xlink:to="lab_us-gaap_DebtInstrumentRedemptionPeriodAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRedemptionPeriodDomain" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtInstrumentRedemptionPeriodDomain" xml:lang="en-US">Debt Instrument, Redemption, Period [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodDomain" xlink:to="lab_us-gaap_DebtInstrumentRedemptionPeriodDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRedemptionPeriodOneMember" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodOneMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtInstrumentRedemptionPeriodOneMember" xml:lang="en-US">Debt Instrument, Redemption, Period One [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodOneMember" xlink:to="lab_us-gaap_DebtInstrumentRedemptionPeriodOneMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DebtInstrumentRedemptionPeriodTwoMember" xlink:label="loc_us-gaap_DebtInstrumentRedemptionPeriodTwoMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DebtInstrumentRedemptionPeriodTwoMember" xml:lang="en-US">Debt Instrument, Redemption, Period Two [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DebtInstrumentRedemptionPeriodTwoMember" xlink:to="lab_us-gaap_DebtInstrumentRedemptionPeriodTwoMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityAxis" xlink:label="loc_us-gaap_CreditFacilityAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CreditFacilityAxis" xml:lang="en-US">Credit Facility [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CreditFacilityAxis" xml:lang="en-US">Credit Facility [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CreditFacilityAxis" xlink:to="lab_us-gaap_CreditFacilityAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CreditFacilityDomain" xlink:label="loc_us-gaap_CreditFacilityDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CreditFacilityDomain" xml:lang="en-US">Credit Facility [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CreditFacilityDomain" xml:lang="en-US">Credit Facility [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CreditFacilityDomain" xlink:to="lab_us-gaap_CreditFacilityDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevolvingCreditFacilityMember" xlink:label="loc_us-gaap_RevolvingCreditFacilityMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RevolvingCreditFacilityMember" xml:lang="en-US">Revolving Credit Facility [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RevolvingCreditFacilityMember" xml:lang="en-US">Revolving Credit Facility</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevolvingCreditFacilityMember" xlink:to="lab_us-gaap_RevolvingCreditFacilityMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableRateAxis" xlink:label="loc_us-gaap_VariableRateAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_VariableRateAxis" xml:lang="en-US">Variable Rate [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_VariableRateAxis" xlink:to="lab_us-gaap_VariableRateAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_VariableRateDomain" xlink:label="loc_us-gaap_VariableRateDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_VariableRateDomain" xml:lang="en-US">Variable Rate [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_VariableRateDomain" xlink:to="lab_us-gaap_VariableRateDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PrimeRateMember" xlink:label="loc_us-gaap_PrimeRateMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PrimeRateMember" xml:lang="en-US">Prime Rate [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PrimeRateMember" xlink:to="lab_us-gaap_PrimeRateMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebt" xlink:label="loc_us-gaap_LongTermDebt" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LongTermDebt" xml:lang="en-US">Long-Term Debt</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_LongTermDebt" xml:lang="en-US">Total debt, net</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebt" xlink:to="lab_us-gaap_LongTermDebt" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_LongTermDebtIncludingRelatedPartyDebtExcludingCurrentMaturities" xlink:label="loc_hmh_LongTermDebtIncludingRelatedPartyDebtExcludingCurrentMaturities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_LongTermDebtIncludingRelatedPartyDebtExcludingCurrentMaturities" xml:lang="en-US">Long-Term Debt Including Related Party Debt, Excluding Current Maturities</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_LongTermDebtIncludingRelatedPartyDebtExcludingCurrentMaturities" xml:lang="en-US">Non-current debt, net</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_LongTermDebtIncludingRelatedPartyDebtExcludingCurrentMaturities" xlink:to="lab_hmh_LongTermDebtIncludingRelatedPartyDebtExcludingCurrentMaturities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_LongTermDebtIncludingRelatedPartyDebtExcludingCurrentMaturities" xml:lang="en-US">Long-Term Debt Including Related Party Debt, Excluding Current Maturities</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MaturitiesOfLongTermDebtAbstract" xlink:label="loc_us-gaap_MaturitiesOfLongTermDebtAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MaturitiesOfLongTermDebtAbstract" xml:lang="en-US">Maturities of Long-Term Debt [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MaturitiesOfLongTermDebtAbstract" xlink:to="lab_us-gaap_MaturitiesOfLongTermDebtAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" xml:lang="en-US">Long-Term Debt, Maturity, Year One</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" xml:lang="en-US">2026</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" xlink:to="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xml:lang="en-US">Long-Term Debt, Maturity, Year Two</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xml:lang="en-US">2027</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xlink:to="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" xml:lang="en-US">Long-Term Debt, Maturity, Year Three</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" xml:lang="en-US">2028</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" xlink:to="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" xml:lang="en-US">Long-Term Debt, Maturity, Year Four</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" xml:lang="en-US">2029</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" xlink:to="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" xml:lang="en-US">Long-Term Debt, Maturity, Year Five</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" xml:lang="en-US">2030</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" xlink:to="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive" xlink:label="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive" xml:lang="en-US">Long-Term Debt, Maturity, after Year Five</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive" xml:lang="en-US">Thereafter</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive" xlink:to="lab_us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable" xml:lang="en-US">Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable" xml:lang="en-US">Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable" xlink:to="lab_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems" xml:lang="en-US">Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems" xml:lang="en-US">Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems" xlink:to="lab_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueRemainingPerformanceObligation" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligation" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RevenueRemainingPerformanceObligation" xml:lang="en-US">Revenue, Remaining Performance Obligation, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RevenueRemainingPerformanceObligation" xml:lang="en-US">Performance obligation, amount</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligation" xlink:to="lab_us-gaap_RevenueRemainingPerformanceObligation" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1" xlink:label="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1" xml:lang="en-US">Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1" xml:lang="en-US">Performance obligation, period</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1" xlink:to="lab_us-gaap_RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludedInBeginningBalance" xlink:label="loc_hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludedInBeginningBalance" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludedInBeginningBalance" xml:lang="en-US">Contract with Customer, Liability, Revenue Recognized Included In Beginning Balance</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludedInBeginningBalance" xml:lang="en-US">Revenue recognized included in contract liabilities balance</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludedInBeginningBalance" xlink:to="lab_hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludedInBeginningBalance" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludedInBeginningBalance" xml:lang="en-US">Contract with Customer, Liability, Revenue Recognized Included In Beginning Balance</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ProjectAndOtherManufacturingContractsMember" xlink:label="loc_hmh_ProjectAndOtherManufacturingContractsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ProjectAndOtherManufacturingContractsMember" xml:lang="en-US">Project And Other Manufacturing Contracts [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ProjectAndOtherManufacturingContractsMember" xml:lang="en-US">Project and other manufacturing contracts revenue</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ProjectAndOtherManufacturingContractsMember" xlink:to="lab_hmh_ProjectAndOtherManufacturingContractsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ProjectAndOtherManufacturingContractsMember" xml:lang="en-US">Project And Other Manufacturing Contracts</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ProductSalesMember" xlink:label="loc_hmh_ProductSalesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ProductSalesMember" xml:lang="en-US">Product Sales [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ProductSalesMember" xml:lang="en-US">Sale of products</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ProductSalesMember" xlink:to="lab_hmh_ProductSalesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ProductSalesMember" xml:lang="en-US">Product Sales</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ProductIncludingRelatedPartyMember" xlink:label="loc_hmh_ProductIncludingRelatedPartyMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ProductIncludingRelatedPartyMember" xml:lang="en-US">Product Including Related Party [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ProductIncludingRelatedPartyMember" xml:lang="en-US">Product revenue</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ProductIncludingRelatedPartyMember" xlink:to="lab_hmh_ProductIncludingRelatedPartyMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ProductIncludingRelatedPartyMember" xml:lang="en-US">Product Including Related Party</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TimingOfTransferOfGoodOrServiceAxis" xlink:label="loc_us-gaap_TimingOfTransferOfGoodOrServiceAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TimingOfTransferOfGoodOrServiceAxis" xml:lang="en-US">Timing of Transfer of Good or Service [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_TimingOfTransferOfGoodOrServiceAxis" xml:lang="en-US">Timing of Transfer of Good or Service [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TimingOfTransferOfGoodOrServiceAxis" xlink:to="lab_us-gaap_TimingOfTransferOfGoodOrServiceAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TimingOfTransferOfGoodOrServiceDomain" xlink:label="loc_us-gaap_TimingOfTransferOfGoodOrServiceDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TimingOfTransferOfGoodOrServiceDomain" xml:lang="en-US">Timing of Transfer of Good or Service [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_TimingOfTransferOfGoodOrServiceDomain" xml:lang="en-US">Timing of Transfer of Good or Service [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TimingOfTransferOfGoodOrServiceDomain" xlink:to="lab_us-gaap_TimingOfTransferOfGoodOrServiceDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransferredOverTimeMember" xlink:label="loc_us-gaap_TransferredOverTimeMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TransferredOverTimeMember" xml:lang="en-US">Transferred over Time [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_TransferredOverTimeMember" xml:lang="en-US">Transferred overtime</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TransferredOverTimeMember" xlink:to="lab_us-gaap_TransferredOverTimeMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_TransferredAtPointInTimeMember" xlink:label="loc_us-gaap_TransferredAtPointInTimeMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_TransferredAtPointInTimeMember" xml:lang="en-US">Transferred at Point in Time [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_TransferredAtPointInTimeMember" xml:lang="en-US">Transferred at point in time</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TransferredAtPointInTimeMember" xlink:to="lab_us-gaap_TransferredAtPointInTimeMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ContractWithCustomerAssetAndLiabilityTable" xlink:label="loc_hmh_ContractWithCustomerAssetAndLiabilityTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ContractWithCustomerAssetAndLiabilityTable" xml:lang="en-US">Contract With Customer Asset And Liability [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ContractWithCustomerAssetAndLiabilityTable" xlink:to="lab_hmh_ContractWithCustomerAssetAndLiabilityTable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ContractWithCustomerAssetAndLiabilityLineItems" xlink:label="loc_hmh_ContractWithCustomerAssetAndLiabilityLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ContractWithCustomerAssetAndLiabilityLineItems" xml:lang="en-US">Contract With Customer Asset And Liability [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ContractWithCustomerAssetAndLiabilityLineItems" xlink:to="lab_hmh_ContractWithCustomerAssetAndLiabilityLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerAssetNet" xlink:label="loc_us-gaap_ContractWithCustomerAssetNet" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ContractWithCustomerAssetNet" xml:lang="en-US">Contract with Customer, Asset, after Allowance for Credit Loss</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_ContractWithCustomerAssetNet" xml:lang="en-US">Beginning balance</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_ContractWithCustomerAssetNet" xml:lang="en-US">Ending balance</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ContractWithCustomerAssetNet" xlink:to="lab_us-gaap_ContractWithCustomerAssetNet" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ContractWithCustomerAssetAdditions" xlink:label="loc_hmh_ContractWithCustomerAssetAdditions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ContractWithCustomerAssetAdditions" xml:lang="en-US">Contract with Customer, Asset, Additions</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ContractWithCustomerAssetAdditions" xml:lang="en-US">Additions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ContractWithCustomerAssetAdditions" xlink:to="lab_hmh_ContractWithCustomerAssetAdditions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ContractWithCustomerAssetAdditions" xml:lang="en-US">Contract with Customer, Asset, Additions</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerAssetReclassifiedToReceivable" xlink:label="loc_us-gaap_ContractWithCustomerAssetReclassifiedToReceivable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ContractWithCustomerAssetReclassifiedToReceivable" xml:lang="en-US">Contract with Customer, Asset, Reclassified to Receivable</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_ContractWithCustomerAssetReclassifiedToReceivable" xml:lang="en-US">Transfers to accounts receivable</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ContractWithCustomerAssetReclassifiedToReceivable" xlink:to="lab_us-gaap_ContractWithCustomerAssetReclassifiedToReceivable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerAssetCreditLossExpense" xlink:label="loc_us-gaap_ContractWithCustomerAssetCreditLossExpense" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ContractWithCustomerAssetCreditLossExpense" xml:lang="en-US">Contract with Customer, Asset, Credit Loss Expense (Reversal)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ContractWithCustomerAssetCreditLossExpense" xml:lang="en-US">Written off</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ContractWithCustomerAssetCreditLossExpense" xlink:to="lab_us-gaap_ContractWithCustomerAssetCreditLossExpense" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ContractWithCustomerLiability" xlink:label="loc_us-gaap_ContractWithCustomerLiability" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ContractWithCustomerLiability" xml:lang="en-US">Contract with Customer, Liability</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_ContractWithCustomerLiability" xml:lang="en-US">Beginning balance</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_ContractWithCustomerLiability" xml:lang="en-US">Ending balance</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ContractWithCustomerLiability" xlink:to="lab_us-gaap_ContractWithCustomerLiability" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ContractWithCustomerLiabilityAdditions" xlink:label="loc_hmh_ContractWithCustomerLiabilityAdditions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ContractWithCustomerLiabilityAdditions" xml:lang="en-US">Contract with Customer, Liability, Additions</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ContractWithCustomerLiabilityAdditions" xml:lang="en-US">Additions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ContractWithCustomerLiabilityAdditions" xlink:to="lab_hmh_ContractWithCustomerLiabilityAdditions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ContractWithCustomerLiabilityAdditions" xml:lang="en-US">Contract with Customer, Liability, Additions</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludingOpeningBalance" xlink:label="loc_hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludingOpeningBalance" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludingOpeningBalance" xml:lang="en-US">Contract with Customer, Liability, Revenue Recognized Including Opening Balance</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludingOpeningBalance" xml:lang="en-US">Revenue recognized</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludingOpeningBalance" xlink:to="lab_hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludingOpeningBalance" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludingOpeningBalance" xml:lang="en-US">Contract with Customer, Liability, Revenue Recognized Including Opening Balance</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfAccruedLiabilitiesTable" xlink:label="loc_hmh_ScheduleOfAccruedLiabilitiesTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfAccruedLiabilitiesTable" xml:lang="en-US">schedule of accrued liabilities [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ScheduleOfAccruedLiabilitiesTable" xlink:to="lab_hmh_ScheduleOfAccruedLiabilitiesTable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ScheduleOfAccruedLiabilitiesLineItems" xlink:label="loc_hmh_ScheduleOfAccruedLiabilitiesLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ScheduleOfAccruedLiabilitiesLineItems" xml:lang="en-US">schedule of accrued liabilities [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ScheduleOfAccruedLiabilitiesLineItems" xlink:to="lab_hmh_ScheduleOfAccruedLiabilitiesLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:label="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent" xml:lang="en-US">Employee-related Liabilities, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent" xml:lang="en-US">Accrued payroll and employee related liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeRelatedLiabilitiesCurrent" xlink:to="lab_us-gaap_EmployeeRelatedLiabilitiesCurrent" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_VendorCostsAccrualCurrent" xlink:label="loc_hmh_VendorCostsAccrualCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_VendorCostsAccrualCurrent" xml:lang="en-US">Vendor Costs Accrual, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_VendorCostsAccrualCurrent" xml:lang="en-US">Accrued vendor costs</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_VendorCostsAccrualCurrent" xlink:to="lab_hmh_VendorCostsAccrualCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_VendorCostsAccrualCurrent" xml:lang="en-US">Vendor Costs Accrual, Current</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProductWarrantyAccrualClassifiedCurrent" xlink:label="loc_us-gaap_ProductWarrantyAccrualClassifiedCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProductWarrantyAccrualClassifiedCurrent" xml:lang="en-US">Product Warranty Accrual, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ProductWarrantyAccrualClassifiedCurrent" xml:lang="en-US">Provisions&#8212;warranty</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_ProductWarrantyAccrualClassifiedCurrent" xml:lang="en-US">Beginning balance</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_ProductWarrantyAccrualClassifiedCurrent" xml:lang="en-US">Ending balance</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductWarrantyAccrualClassifiedCurrent" xlink:to="lab_us-gaap_ProductWarrantyAccrualClassifiedCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringReserveCurrent" xlink:label="loc_us-gaap_RestructuringReserveCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RestructuringReserveCurrent" xml:lang="en-US">Restructuring Reserve, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RestructuringReserveCurrent" xml:lang="en-US">Provisions&#8212;restructuring</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringReserveCurrent" xlink:to="lab_us-gaap_RestructuringReserveCurrent" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AccrualForEnvironmentalLossContingenciesCurrent" xlink:label="loc_hmh_AccrualForEnvironmentalLossContingenciesCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AccrualForEnvironmentalLossContingenciesCurrent" xml:lang="en-US">Accrual for Environmental Loss Contingencies, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_AccrualForEnvironmentalLossContingenciesCurrent" xml:lang="en-US">Provisions&#8212;environmental</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AccrualForEnvironmentalLossContingenciesCurrent" xlink:to="lab_hmh_AccrualForEnvironmentalLossContingenciesCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AccrualForEnvironmentalLossContingenciesCurrent" xml:lang="en-US">Accrual for Environmental Loss Contingencies, Current</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LossContingencyAccrualCarryingValueCurrent" xlink:label="loc_us-gaap_LossContingencyAccrualCarryingValueCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LossContingencyAccrualCarryingValueCurrent" xml:lang="en-US">Loss Contingency, Accrual, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_LossContingencyAccrualCarryingValueCurrent" xml:lang="en-US">Provisions for loss contingencies</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LossContingencyAccrualCarryingValueCurrent" xlink:to="lab_us-gaap_LossContingencyAccrualCarryingValueCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_InterestPayableCurrent" xlink:label="loc_us-gaap_InterestPayableCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_InterestPayableCurrent" xml:lang="en-US">Interest Payable, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_InterestPayableCurrent" xml:lang="en-US">Accrued interest</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InterestPayableCurrent" xlink:to="lab_us-gaap_InterestPayableCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SalesAndExciseTaxPayableCurrent" xlink:label="loc_us-gaap_SalesAndExciseTaxPayableCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SalesAndExciseTaxPayableCurrent" xml:lang="en-US">Sales and Excise Tax Payable, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SalesAndExciseTaxPayableCurrent" xml:lang="en-US">Accrued sales and other taxes</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SalesAndExciseTaxPayableCurrent" xlink:to="lab_us-gaap_SalesAndExciseTaxPayableCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherAccruedLiabilitiesCurrent" xlink:label="loc_us-gaap_OtherAccruedLiabilitiesCurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherAccruedLiabilitiesCurrent" xml:lang="en-US">Other Accrued Liabilities, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherAccruedLiabilitiesCurrent" xml:lang="en-US">Other</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherAccruedLiabilitiesCurrent" xlink:to="lab_us-gaap_OtherAccruedLiabilitiesCurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProductWarrantyLiabilityTable" xlink:label="loc_us-gaap_ProductWarrantyLiabilityTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProductWarrantyLiabilityTable" xml:lang="en-US">Product Warranty Liability [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductWarrantyLiabilityTable" xlink:to="lab_us-gaap_ProductWarrantyLiabilityTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProductWarrantyLiabilityLineItems" xlink:label="loc_us-gaap_ProductWarrantyLiabilityLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProductWarrantyLiabilityLineItems" xml:lang="en-US">Product Warranty Liability [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductWarrantyLiabilityLineItems" xlink:to="lab_us-gaap_ProductWarrantyLiabilityLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ProductWarrantyExpense" xlink:label="loc_us-gaap_ProductWarrantyExpense" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ProductWarrantyExpense" xml:lang="en-US">Product Warranty Expense</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ProductWarrantyExpense" xml:lang="en-US">Accrued expense</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_ProductWarrantyExpense" xml:lang="en-US">Warranty expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProductWarrantyExpense" xlink:to="lab_us-gaap_ProductWarrantyExpense" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StandardProductWarrantyAccrualPayments" xlink:label="loc_us-gaap_StandardProductWarrantyAccrualPayments" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StandardProductWarrantyAccrualPayments" xml:lang="en-US">Standard Product Warranty Accrual, Decrease for Payments</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_StandardProductWarrantyAccrualPayments" xml:lang="en-US">Payments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StandardProductWarrantyAccrualPayments" xlink:to="lab_us-gaap_StandardProductWarrantyAccrualPayments" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_StandardProductWarrantyExpenseReversal" xlink:label="loc_hmh_StandardProductWarrantyExpenseReversal" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_StandardProductWarrantyExpenseReversal" xml:lang="en-US">Standard Product Warranty, Expense Reversal</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_StandardProductWarrantyExpenseReversal" xml:lang="en-US">Provision reversed during the period</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_StandardProductWarrantyExpenseReversal" xlink:to="lab_hmh_StandardProductWarrantyExpenseReversal" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_StandardProductWarrantyExpenseReversal" xml:lang="en-US">Standard Product Warranty, Expense Reversal</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StandardProductWarrantyAccrualForeignCurrencyTranslationGainLoss" xlink:label="loc_us-gaap_StandardProductWarrantyAccrualForeignCurrencyTranslationGainLoss" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StandardProductWarrantyAccrualForeignCurrencyTranslationGainLoss" xml:lang="en-US">Standard Product Warranty Accrual, Foreign Currency Translation Gain (Loss)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_StandardProductWarrantyAccrualForeignCurrencyTranslationGainLoss" xml:lang="en-US">Currency translation differences</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StandardProductWarrantyAccrualForeignCurrencyTranslationGainLoss" xlink:to="lab_us-gaap_StandardProductWarrantyAccrualForeignCurrencyTranslationGainLoss" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ProductWarrantyReclassification" xlink:label="loc_hmh_ProductWarrantyReclassification" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ProductWarrantyReclassification" xml:lang="en-US">Product Warranty Reclassification</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ProductWarrantyReclassification" xlink:to="lab_hmh_ProductWarrantyReclassification" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ProductWarrantyReclassification" xml:lang="en-US">Product Warranty Reclassification</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AccruedWarrantLiabilityExpenses" xlink:label="loc_hmh_AccruedWarrantLiabilityExpenses" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AccruedWarrantLiabilityExpenses" xml:lang="en-US">Accrued Warrant Liability Expenses</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_AccruedWarrantLiabilityExpenses" xml:lang="en-US">Accrued expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AccruedWarrantLiabilityExpenses" xlink:to="lab_hmh_AccruedWarrantLiabilityExpenses" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AccruedWarrantLiabilityExpenses" xml:lang="en-US">Accrued warrant liability expenses.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DrillformMember" xlink:label="loc_hmh_DrillformMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DrillformMember" xml:lang="en-US">Drillform [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_DrillformMember" xml:lang="en-US">Drillform</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DrillformMember" xlink:to="lab_hmh_DrillformMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DrillformMember" xml:lang="en-US">Drillform</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent" xlink:label="loc_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent" xml:lang="en-US">Liability, Defined Benefit Plan, Noncurrent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent" xml:lang="en-US">Pension and other post&#8212;retirement liabilities</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent" xml:lang="en-US">Non-current&#160;liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent" xlink:to="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxLiabilities" xlink:label="loc_us-gaap_DeferredTaxLiabilities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredTaxLiabilities" xml:lang="en-US">Deferred Tax Liabilities, Net</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredTaxLiabilities" xml:lang="en-US">Deferred tax liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxLiabilities" xlink:to="lab_us-gaap_DeferredTaxLiabilities" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent" xlink:label="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent" xml:lang="en-US">Business Combination, Contingent Consideration, Liability, Noncurrent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent" xml:lang="en-US">Contingent considerations&#8212;related party</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent" xml:lang="en-US">Contingent consideration</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent" xlink:to="lab_us-gaap_BusinessCombinationContingentConsiderationLiabilityNoncurrent" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ProvisionsNoncurrent" xlink:label="loc_hmh_ProvisionsNoncurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ProvisionsNoncurrent" xml:lang="en-US">Provisions, Noncurrent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ProvisionsNoncurrent" xml:lang="en-US">Provisions long-term</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ProvisionsNoncurrent" xlink:to="lab_hmh_ProvisionsNoncurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ProvisionsNoncurrent" xml:lang="en-US">Provisions, Noncurrent</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_TaxReceivableAgreementLiabilityNoncurrent" xlink:label="loc_hmh_TaxReceivableAgreementLiabilityNoncurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_TaxReceivableAgreementLiabilityNoncurrent" xml:lang="en-US">Tax Receivable Agreement Liability, Noncurrent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_TaxReceivableAgreementLiabilityNoncurrent" xml:lang="en-US">Tax receivable agreement liability</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_TaxReceivableAgreementLiabilityNoncurrent" xlink:to="lab_hmh_TaxReceivableAgreementLiabilityNoncurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_TaxReceivableAgreementLiabilityNoncurrent" xml:lang="en-US">Tax Receivable Agreement Liability, Noncurrent</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherSundryLiabilitiesNoncurrent" xlink:label="loc_us-gaap_OtherSundryLiabilitiesNoncurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherSundryLiabilitiesNoncurrent" xml:lang="en-US">Other Sundry Liabilities, Noncurrent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OtherSundryLiabilitiesNoncurrent" xml:lang="en-US">Other long-term liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherSundryLiabilitiesNoncurrent" xlink:to="lab_us-gaap_OtherSundryLiabilitiesNoncurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherLiabilitiesAbstract" xlink:label="loc_us-gaap_OtherLiabilitiesAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherLiabilitiesAbstract" xml:lang="en-US">Other Liabilities [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherLiabilitiesAbstract" xlink:to="lab_us-gaap_OtherLiabilitiesAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterestTable" xlink:label="loc_us-gaap_MinorityInterestTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MinorityInterestTable" xml:lang="en-US">Noncontrolling Interest [Table]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_MinorityInterestTable" xml:lang="en-US">Noncontrolling Interest [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MinorityInterestTable" xlink:to="lab_us-gaap_MinorityInterestTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MinorityInterestLineItems" xlink:label="loc_us-gaap_MinorityInterestLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MinorityInterestLineItems" xml:lang="en-US">Noncontrolling Interest [Line Items]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_MinorityInterestLineItems" xml:lang="en-US">Noncontrolling Interest [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MinorityInterestLineItems" xlink:to="lab_us-gaap_MinorityInterestLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PreferredStockSharesAuthorized" xml:lang="en-US">Preferred Stock, Shares Authorized</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PreferredStockSharesAuthorized" xml:lang="en-US">Preferred stock, shares authorized (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockSharesAuthorized" xlink:to="lab_us-gaap_PreferredStockSharesAuthorized" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" xlink:label="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" xml:lang="en-US">Stockholders' Equity Note, Stock Split, Conversion Ratio</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" xml:lang="en-US">Stock split, conversion ratio</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" xlink:to="lab_us-gaap_StockholdersEquityNoteStockSplitConversionRatio1" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConversionOfStockSharesConverted1" xlink:label="loc_us-gaap_ConversionOfStockSharesConverted1" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ConversionOfStockSharesConverted1" xml:lang="en-US">Conversion of Stock, Shares Converted</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ConversionOfStockSharesConverted1" xml:lang="en-US">Conversion of stock, shares converted (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConversionOfStockSharesConverted1" xlink:to="lab_us-gaap_ConversionOfStockSharesConverted1" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_CommonStockConversionRatio" xlink:label="loc_hmh_CommonStockConversionRatio" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_CommonStockConversionRatio" xml:lang="en-US">Common Stock, Conversion Ratio</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_CommonStockConversionRatio" xml:lang="en-US">Common Stock, Conversion Ratio</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_CommonStockConversionRatio" xlink:to="lab_hmh_CommonStockConversionRatio" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_CommonStockConversionRatio" xml:lang="en-US">Common Stock, Conversion Ratio</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ConversionOfStockSharesIssued1" xlink:label="loc_us-gaap_ConversionOfStockSharesIssued1" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ConversionOfStockSharesIssued1" xml:lang="en-US">Conversion of Stock, Shares Issued</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ConversionOfStockSharesIssued1" xml:lang="en-US">Conversion of stock, shares issued (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConversionOfStockSharesIssued1" xlink:to="lab_us-gaap_ConversionOfStockSharesIssued1" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_CommonStockConvertibleSharesIssuable" xlink:label="loc_hmh_CommonStockConvertibleSharesIssuable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_CommonStockConvertibleSharesIssuable" xml:lang="en-US">Common Stock, Convertible, Shares Issuable</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_CommonStockConvertibleSharesIssuable" xml:lang="en-US">Shares issuable (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_CommonStockConvertibleSharesIssuable" xlink:to="lab_hmh_CommonStockConvertibleSharesIssuable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_CommonStockConvertibleSharesIssuable" xml:lang="en-US">Common Stock, Convertible, Shares Issuable</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_NoncontrollingInterestsMember" xlink:label="loc_hmh_NoncontrollingInterestsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_NoncontrollingInterestsMember" xml:lang="en-US">Noncontrolling Interests [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_NoncontrollingInterestsMember" xml:lang="en-US">Noncontrolling Interests</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_NoncontrollingInterestsMember" xlink:to="lab_hmh_NoncontrollingInterestsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_NoncontrollingInterestsMember" xml:lang="en-US">Noncontrolling Interests</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_MovementInMinorityInterestRollForward" xlink:label="loc_us-gaap_MovementInMinorityInterestRollForward" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_MovementInMinorityInterestRollForward" xml:lang="en-US">Equity, Attributable to Noncontrolling Interest [Roll Forward]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_MovementInMinorityInterestRollForward" xml:lang="en-US">Ownership</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_MovementInMinorityInterestRollForward" xlink:to="lab_us-gaap_MovementInMinorityInterestRollForward" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonUnitOutstanding" xlink:label="loc_us-gaap_CommonUnitOutstanding" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonUnitOutstanding" xml:lang="en-US">Common Unit, Outstanding</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_CommonUnitOutstanding" xml:lang="en-US">Beginning balance (in shares)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_CommonUnitOutstanding" xml:lang="en-US">Ending balance (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonUnitOutstanding" xlink:to="lab_us-gaap_CommonUnitOutstanding" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_StockIssuedDuringPeriodSharesAcquisition" xlink:label="loc_hmh_StockIssuedDuringPeriodSharesAcquisition" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_StockIssuedDuringPeriodSharesAcquisition" xml:lang="en-US">Stock Issued During Period, Shares, Acquisition</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_StockIssuedDuringPeriodSharesAcquisition" xml:lang="en-US">Purchase of HMH B.V. Shares (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_StockIssuedDuringPeriodSharesAcquisition" xlink:to="lab_hmh_StockIssuedDuringPeriodSharesAcquisition" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_StockIssuedDuringPeriodSharesAcquisition" xml:lang="en-US">Stock Issued During Period, Shares, Acquisition</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xml:lang="en-US">Stock Issued During Period, Shares, Conversion of Convertible Securities</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xml:lang="en-US">Partial Exercise of Underwriters Purchase Option (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod" xml:lang="en-US">Issuance under the Equity Based Compensation Plan (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriod" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_EquityAttributableToNoncontrollingInterestInterestRollForward" xlink:label="loc_hmh_EquityAttributableToNoncontrollingInterestInterestRollForward" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_EquityAttributableToNoncontrollingInterestInterestRollForward" xml:lang="en-US">Equity, Attributable to Noncontrolling Interest Interest [Roll Forward]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_EquityAttributableToNoncontrollingInterestInterestRollForward" xml:lang="en-US">Ownership Percentage</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_EquityAttributableToNoncontrollingInterestInterestRollForward" xlink:to="lab_hmh_EquityAttributableToNoncontrollingInterestInterestRollForward" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_EquityAttributableToNoncontrollingInterestInterestRollForward" xml:lang="en-US">Equity, Attributable to Noncontrolling Interest Interest</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OwnershipPercentage" xlink:label="loc_hmh_OwnershipPercentage" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OwnershipPercentage" xml:lang="en-US">Ownership Percentage</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_hmh_OwnershipPercentage" xml:lang="en-US">Beginning balance</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_hmh_OwnershipPercentage" xml:lang="en-US">Ending balance</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OwnershipPercentage" xlink:to="lab_hmh_OwnershipPercentage" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_OwnershipPercentage" xml:lang="en-US">Ownership Percentage</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_StockIssuedDuringPeriodSharesAcquisitionsPercent" xlink:label="loc_hmh_StockIssuedDuringPeriodSharesAcquisitionsPercent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_StockIssuedDuringPeriodSharesAcquisitionsPercent" xml:lang="en-US">Stock Issued During Period, Shares, Acquisitions, Percent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_StockIssuedDuringPeriodSharesAcquisitionsPercent" xml:lang="en-US">Purchase of HMH B.V. Shares</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_StockIssuedDuringPeriodSharesAcquisitionsPercent" xlink:to="lab_hmh_StockIssuedDuringPeriodSharesAcquisitionsPercent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_StockIssuedDuringPeriodSharesAcquisitionsPercent" xml:lang="en-US">Stock Issued During Period, Shares, Acquisitions, Percent</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_StockIssuedDuringPeriodSharesConversionOfConvertibleSecuritiesPercent" xlink:label="loc_hmh_StockIssuedDuringPeriodSharesConversionOfConvertibleSecuritiesPercent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_StockIssuedDuringPeriodSharesConversionOfConvertibleSecuritiesPercent" xml:lang="en-US">Stock Issued During Period, Shares, Conversion of Convertible Securities, Percent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_StockIssuedDuringPeriodSharesConversionOfConvertibleSecuritiesPercent" xml:lang="en-US">Partial Exercise of Underwriters Purchase Option</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_StockIssuedDuringPeriodSharesConversionOfConvertibleSecuritiesPercent" xlink:to="lab_hmh_StockIssuedDuringPeriodSharesConversionOfConvertibleSecuritiesPercent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_StockIssuedDuringPeriodSharesConversionOfConvertibleSecuritiesPercent" xml:lang="en-US">Stock Issued During Period, Shares, Conversion of Convertible Securities, Percent</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriodPercent" xlink:label="loc_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriodPercent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriodPercent" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period, Percent</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriodPercent" xml:lang="en-US">Issuance under the Equity Based Compensation Plan</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriodPercent" xlink:to="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriodPercent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesIssuedInPeriodPercent" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period, Percent</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfStockByClassTable" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfStockByClassTable" xml:lang="en-US">Stock, Class of Stock [Table]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfStockByClassTable" xml:lang="en-US">Stock, Class of Stock [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable" xlink:to="lab_us-gaap_ScheduleOfStockByClassTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember" xlink:label="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember" xml:lang="en-US">Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember" xml:lang="en-US">Hedging reserve adjustments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember" xlink:to="lab_us-gaap_AccumulatedGainLossNetCashFlowHedgeParentMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" xlink:label="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" xml:lang="en-US">Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" xml:lang="en-US">Pension remeasurement reserve adjustments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" xlink:to="lab_us-gaap_AccumulatedDefinedBenefitPlansAdjustmentMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AccumulatedTranslationAdjustmentMember" xlink:label="loc_us-gaap_AccumulatedTranslationAdjustmentMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AccumulatedTranslationAdjustmentMember" xml:lang="en-US">Accumulated Foreign Currency Adjustment Attributable to Parent [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AccumulatedTranslationAdjustmentMember" xml:lang="en-US">Currency translation reserve adjustments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccumulatedTranslationAdjustmentMember" xlink:to="lab_us-gaap_AccumulatedTranslationAdjustmentMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ClassOfStockLineItems" xlink:label="loc_us-gaap_ClassOfStockLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ClassOfStockLineItems" xml:lang="en-US">Class of Stock [Line Items]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ClassOfStockLineItems" xml:lang="en-US">Class of Stock [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfStockLineItems" xlink:to="lab_us-gaap_ClassOfStockLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xml:lang="en-US">Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xml:lang="en-US">Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" xlink:to="lab_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AwardTypeAxis" xlink:label="loc_us-gaap_AwardTypeAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AwardTypeAxis" xml:lang="en-US">Award Type [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AwardTypeAxis" xml:lang="en-US">Award Type [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AwardTypeAxis" xlink:to="lab_us-gaap_AwardTypeAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xml:lang="en-US">Award Type [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xml:lang="en-US">Award Type [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestrictedStockUnitsRSUMember" xlink:label="loc_us-gaap_RestrictedStockUnitsRSUMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RestrictedStockUnitsRSUMember" xml:lang="en-US">Restricted Stock Units (RSUs) [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RestrictedStockUnitsRSUMember" xml:lang="en-US">Restricted common stock</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestrictedStockUnitsRSUMember" xlink:to="lab_us-gaap_RestrictedStockUnitsRSUMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PerformanceSharesMember" xlink:label="loc_us-gaap_PerformanceSharesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PerformanceSharesMember" xml:lang="en-US">Performance Shares [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PerformanceSharesMember" xml:lang="en-US">Performance Share Units</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="lab_us-gaap_PerformanceSharesMember" xml:lang="en-US">Performance share units</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PerformanceSharesMember" xlink:to="lab_us-gaap_PerformanceSharesMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockCompensationPlanMember" xlink:label="loc_us-gaap_StockCompensationPlanMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockCompensationPlanMember" xml:lang="en-US">Share-Based Payment Arrangement [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockCompensationPlanMember" xlink:to="lab_us-gaap_StockCompensationPlanMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StatementOfIncomeLocationBalanceAxis" xlink:label="loc_us-gaap_StatementOfIncomeLocationBalanceAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StatementOfIncomeLocationBalanceAxis" xml:lang="en-US">Location, Statement of Income, Balance [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StatementOfIncomeLocationBalanceAxis" xml:lang="en-US">Location, Statement of Income, Balance [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfIncomeLocationBalanceAxis" xlink:to="lab_us-gaap_StatementOfIncomeLocationBalanceAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" xlink:label="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" xml:lang="en-US">Common Stock, Capital Shares Reserved for Future Issuance</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" xml:lang="en-US">Common stock, capital shares reserved for future issuance (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" xlink:to="lab_us-gaap_CommonStockCapitalSharesReservedForFutureIssuance" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xml:lang="en-US">Shares available for issuance (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardShareReserveAnnualPercentageIncrease" xlink:label="loc_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardShareReserveAnnualPercentageIncrease" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardShareReserveAnnualPercentageIncrease" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Share Reserve, Annual Percentage Increase</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardShareReserveAnnualPercentageIncrease" xml:lang="en-US">Annual increase percentage (up to)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardShareReserveAnnualPercentageIncrease" xlink:to="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardShareReserveAnnualPercentageIncrease" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardShareReserveAnnualPercentageIncrease" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Share Reserve, Annual Percentage Increase</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" xml:lang="en-US">Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" xml:lang="en-US">Unrecognized compensation cost</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xml:lang="en-US">Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xml:lang="en-US">Recognition period</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" xml:lang="en-US">Vesting period</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePeriod" xlink:label="loc_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePeriod" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePeriod" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Performance Period</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePeriod" xml:lang="en-US">Performance period</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePeriod" xlink:to="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePeriod" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePeriod" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Performance Period</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePayoutPercentage" xlink:label="loc_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePayoutPercentage" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePayoutPercentage" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Performance Payout Percentage</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePayoutPercentage" xml:lang="en-US">Payout percentage</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePayoutPercentage" xlink:to="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePayoutPercentage" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformancePayoutPercentage" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Performance Payout Percentage</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount" xml:lang="en-US">Share-Based Payment Arrangement, Amount Capitalized</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount" xml:lang="en-US">Program for management</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount" xlink:to="lab_us-gaap_EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_FairValueShareBasedPaymentArrangementAward" xlink:label="loc_hmh_FairValueShareBasedPaymentArrangementAward" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_FairValueShareBasedPaymentArrangementAward" xml:lang="en-US">Fair Value Share Based Payment Arrangement Award</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_FairValueShareBasedPaymentArrangementAward" xml:lang="en-US">Fair value share based payment arrangement award</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_FairValueShareBasedPaymentArrangementAward" xlink:to="lab_hmh_FairValueShareBasedPaymentArrangementAward" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_FairValueShareBasedPaymentArrangementAward" xml:lang="en-US">Fair value share based payment arrangement award.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationGross" xlink:label="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationGross" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationGross" xml:lang="en-US">Shares Granted, Value, Share-Based Payment Arrangement, before Forfeiture</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationGross" xml:lang="en-US">Share-based payment arrangement, before forfeiture</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationGross" xlink:to="lab_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationGross" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationForfeited" xlink:label="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationForfeited" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationForfeited" xml:lang="en-US">Shares Granted, Value, Share-Based Payment Arrangement, Forfeited</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationForfeited" xml:lang="en-US">Share-based payment arrangement, forfeited</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationForfeited" xlink:to="lab_us-gaap_StockGrantedDuringPeriodValueSharebasedCompensationForfeited" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ProgramAxis" xlink:label="loc_hmh_ProgramAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ProgramAxis" xml:lang="en-US">Program [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ProgramAxis" xlink:to="lab_hmh_ProgramAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ProgramAxis" xml:lang="en-US">Program.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ProgramDomain" xlink:label="loc_hmh_ProgramDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ProgramDomain" xml:lang="en-US">Program [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ProgramDomain" xlink:to="lab_hmh_ProgramDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ProgramDomain" xml:lang="en-US">Program.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_FoundersPhantomEquityAwardProgramMember" xlink:label="loc_hmh_FoundersPhantomEquityAwardProgramMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_FoundersPhantomEquityAwardProgramMember" xml:lang="en-US">Founders Phantom Equity Award Program [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_FoundersPhantomEquityAwardProgramMember" xml:lang="en-US">Founders phantom equity award program</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_FoundersPhantomEquityAwardProgramMember" xlink:to="lab_hmh_FoundersPhantomEquityAwardProgramMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_FoundersPhantomEquityAwardProgramMember" xml:lang="en-US">Founders phantom equity award program.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_LongTermIncentiveProgramMember" xlink:label="loc_hmh_LongTermIncentiveProgramMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_LongTermIncentiveProgramMember" xml:lang="en-US">Long Term Incentive Program [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_LongTermIncentiveProgramMember" xml:lang="en-US">Long term incentive program</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_LongTermIncentiveProgramMember" xlink:to="lab_hmh_LongTermIncentiveProgramMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_LongTermIncentiveProgramMember" xml:lang="en-US">Long term incentive program.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xml:lang="en-US">Shares of Restricted Common Stock/Performance Share Units</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedRollForward" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xml:lang="en-US">Beginning balance (in shares)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xml:lang="en-US">Ending balance (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtIPO" xlink:label="loc_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtIPO" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtIPO" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Converted At IPO</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtIPO" xml:lang="en-US">Converted at IPO (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtIPO" xlink:to="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtIPO" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtIPO" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Converted At IPO</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xml:lang="en-US">Post-IPO grant (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xml:lang="en-US">Vested upon the consummation of the IPO (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" xml:lang="en-US">Weighted Average Price on the Date of Grant</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xml:lang="en-US">Beginning balance (in dollars per share)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xml:lang="en-US">Ending balance (in dollars per share)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValue" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtIPOInPeriod" xlink:label="loc_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtIPOInPeriod" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtIPOInPeriod" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Converted At IPO in Period,</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtIPOInPeriod" xml:lang="en-US">Converted at IPO (in dollars per share)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtIPOInPeriod" xlink:to="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtIPOInPeriod" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedAtIPOInPeriod" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Converted At IPO in Period, Weighted Average Grant Date Fair Value</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xml:lang="en-US">Post-IPO grant (in dollars per share)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue" xml:lang="en-US">Vested upon the consummation of the IPO (in dollars per share)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodWeightedAverageGrantDateFairValue" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue" xml:lang="en-US">Total grant date fair value of restricted stock awards that vested</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" xml:lang="en-US">Risk free interest rate</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsRiskFreeInterestRate" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" xml:lang="en-US">Stock price volatility</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Term</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" xml:lang="en-US">Contracted term in years</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" xlink:to="lab_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExpectedTerm1" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate" xml:lang="en-US">Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate" xml:lang="en-US">Expected dividend yield</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate" xlink:to="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedDividendRate" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SharePrice" xlink:label="loc_us-gaap_SharePrice" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SharePrice" xml:lang="en-US">Share Price</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_SharePrice" xml:lang="en-US">Grant date price of HMH common stock (in dollars per share)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharePrice" xlink:to="lab_us-gaap_SharePrice" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanServiceCost" xlink:label="loc_us-gaap_DefinedBenefitPlanServiceCost" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanServiceCost" xml:lang="en-US">Defined Benefit Plan, Service Cost</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanServiceCost" xml:lang="en-US">Service cost</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanServiceCost" xlink:to="lab_us-gaap_DefinedBenefitPlanServiceCost" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanInterestCost" xlink:label="loc_us-gaap_DefinedBenefitPlanInterestCost" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanInterestCost" xml:lang="en-US">Defined Benefit Plan, Interest Cost</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanInterestCost" xml:lang="en-US">Interest cost</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanInterestCost" xlink:to="lab_us-gaap_DefinedBenefitPlanInterestCost" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xlink:label="loc_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xml:lang="en-US">Defined Benefit Plan, Amortization of Gain (Loss)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xml:lang="en-US">Amortization of net actuarial loss</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xml:lang="en-US">Amortization of net actuarial loss</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xlink:to="lab_us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xlink:label="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xml:lang="en-US">Defined Benefit Plan, Net Periodic Benefit Cost (Credit)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xml:lang="en-US">Net periodic cost</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xml:lang="en-US">Net periodic cost</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xlink:to="lab_us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanAbstract" xml:lang="en-US">Defined Benefit Plan [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAbstract" xlink:to="lab_us-gaap_DefinedBenefitPlanAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanRollForwardsAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanRollForwardsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanRollForwardsAbstract" xml:lang="en-US">Defined Benefit Plan, Roll Forwards [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanRollForwardsAbstract" xlink:to="lab_us-gaap_DefinedBenefitPlanRollForwardsAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanBenefitObligation" xlink:label="loc_us-gaap_DefinedBenefitPlanBenefitObligation" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligation" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligation" xml:lang="en-US">Beginning balance</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligation" xml:lang="en-US">Ending balance</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanBenefitObligation" xlink:to="lab_us-gaap_DefinedBenefitPlanBenefitObligation" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanActuarialGainLoss" xlink:label="loc_us-gaap_DefinedBenefitPlanActuarialGainLoss" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanActuarialGainLoss" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanActuarialGainLoss" xml:lang="en-US">Actuarial (gain) loss</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanActuarialGainLoss" xlink:to="lab_us-gaap_DefinedBenefitPlanActuarialGainLoss" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xlink:label="loc_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Benefits Paid</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xml:lang="en-US">Benefits paid</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" xlink:to="lab_us-gaap_DefinedBenefitPlanBenefitObligationBenefitsPaid" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation" xlink:label="loc_us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation" xml:lang="en-US">Foreign currency translation adjustment</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation" xlink:to="lab_us-gaap_DefinedBenefitPlanForeignCurrencyExchangeRateChangesBenefitObligation" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanOtherChanges" xlink:label="loc_us-gaap_DefinedBenefitPlanOtherChanges" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanOtherChanges" xml:lang="en-US">Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Other Change</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanOtherChanges" xml:lang="en-US">Other</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanOtherChanges" xlink:to="lab_us-gaap_DefinedBenefitPlanOtherChanges" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:label="loc_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xml:lang="en-US">Beginning of year</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xml:lang="en-US">End of year</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:to="lab_us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanContributionsByEmployer" xlink:label="loc_us-gaap_DefinedBenefitPlanContributionsByEmployer" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Contributions by Employer</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer" xml:lang="en-US">Employer contribution</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanContributionsByEmployer" xlink:to="lab_us-gaap_DefinedBenefitPlanContributionsByEmployer" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" xlink:label="loc_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" xml:lang="en-US">Defined Benefit Plan, Plan Assets, Benefits Paid</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" xml:lang="en-US">Benefits paid</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" xlink:to="lab_us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanFundedStatusOfPlan" xlink:label="loc_us-gaap_DefinedBenefitPlanFundedStatusOfPlan" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan" xml:lang="en-US">Defined Benefit Plan, Funded (Unfunded) Status of Plan</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan" xml:lang="en-US">Funded status&#8212;End of year</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanFundedStatusOfPlan" xlink:to="lab_us-gaap_DefinedBenefitPlanFundedStatusOfPlan" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation" xlink:label="loc_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation" xml:lang="en-US">Defined Benefit Plan, Accumulated Benefit Obligation</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation" xml:lang="en-US">Accumulated benefit obligation</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation" xlink:to="lab_us-gaap_DefinedBenefitPlanAccumulatedBenefitObligation" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheetAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheetAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheetAbstract" xml:lang="en-US">Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheetAbstract" xlink:to="lab_us-gaap_DefinedBenefitPlanAmountsRecognizedInBalanceSheetAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansNoncurrentLiabilitiesAbstract" xlink:label="loc_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansNoncurrentLiabilitiesAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansNoncurrentLiabilitiesAbstract" xml:lang="en-US">Liability, Defined Benefit Plan [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansNoncurrentLiabilitiesAbstract" xml:lang="en-US">Pension benefits</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansNoncurrentLiabilitiesAbstract" xlink:to="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansNoncurrentLiabilitiesAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities" xlink:label="loc_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities" xml:lang="en-US">Liability, Defined Benefit Plan, Current</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities" xml:lang="en-US">Current liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities" xlink:to="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent" xlink:label="loc_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent" xml:lang="en-US">Liability, Defined Benefit Plan</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent" xml:lang="en-US">Net amount recognized</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent" xlink:to="lab_us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PlanNameAxis" xlink:label="loc_us-gaap_PlanNameAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PlanNameAxis" xml:lang="en-US">Plan Name [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PlanNameAxis" xlink:to="lab_us-gaap_PlanNameAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PlanNameDomain" xlink:label="loc_us-gaap_PlanNameDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PlanNameDomain" xml:lang="en-US">Plan Name [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PlanNameDomain" xlink:to="lab_us-gaap_PlanNameDomain" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_PensionBenefitsMember" xlink:label="loc_hmh_PensionBenefitsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_PensionBenefitsMember" xml:lang="en-US">Pension Benefits [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_PensionBenefitsMember" xlink:to="lab_hmh_PensionBenefitsMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract" xml:lang="en-US">Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract" xml:lang="en-US">Pension benefits</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract" xlink:to="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation" xlink:label="loc_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation" xml:lang="en-US">Defined Benefit Plan, Pension Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Projected Benefit Obligation</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation" xml:lang="en-US">Projected benefit obligation</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation" xlink:to="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateProjectedBenefitObligation" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation" xlink:label="loc_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation" xml:lang="en-US">Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets, Accumulated Benefit Obligation</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation" xml:lang="en-US">Accumulated benefit obligation</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation" xlink:to="lab_us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract" xml:lang="en-US">Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract" xlink:to="lab_us-gaap_DefinedBenefitPlanWeightedAverageAssumptionsUsedInCalculatingNetPeriodicBenefitCostAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetirementPlanNameAxis" xlink:label="loc_us-gaap_RetirementPlanNameAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RetirementPlanNameAxis" xml:lang="en-US">Retirement Plan Name [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetirementPlanNameAxis" xlink:to="lab_us-gaap_RetirementPlanNameAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RetirementPlanNameDomain" xlink:label="loc_us-gaap_RetirementPlanNameDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RetirementPlanNameDomain" xml:lang="en-US">Retirement Plan Name [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetirementPlanNameDomain" xlink:to="lab_us-gaap_RetirementPlanNameDomain" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_GermanPlanMember" xlink:label="loc_hmh_GermanPlanMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_GermanPlanMember" xml:lang="en-US">German Plan [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_GermanPlanMember" xml:lang="en-US">German Plan [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_GermanPlanMember" xlink:to="lab_hmh_GermanPlanMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_GermanPlanMember" xml:lang="en-US">German plan.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_NorwegianPlanMember" xlink:label="loc_hmh_NorwegianPlanMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_NorwegianPlanMember" xml:lang="en-US">Norwegian Plan [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_NorwegianPlanMember" xml:lang="en-US">Norwegian Plan [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_NorwegianPlanMember" xlink:to="lab_hmh_NorwegianPlanMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_NorwegianPlanMember" xml:lang="en-US">Norwegian plan.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate" xlink:label="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate" xml:lang="en-US">Discount rate</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate" xlink:to="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" xlink:label="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-Term Rate of Return on Plan Assets</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" xml:lang="en-US">Expected long-term return on plan assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" xlink:to="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostWeightedAverageInterestCreditingRate" xlink:label="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostWeightedAverageInterestCreditingRate" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostWeightedAverageInterestCreditingRate" xml:lang="en-US">Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Weighted-Average Interest Crediting Rate</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostWeightedAverageInterestCreditingRate" xml:lang="en-US">Interest crediting rate</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostWeightedAverageInterestCreditingRate" xlink:to="lab_us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostWeightedAverageInterestCreditingRate" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax" xlink:label="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax" xml:lang="en-US">Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax" xml:lang="en-US">Actuarial (gain) loss</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax" xlink:to="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_LifeExpectancyCategoryAxis" xlink:label="loc_hmh_LifeExpectancyCategoryAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_LifeExpectancyCategoryAxis" xml:lang="en-US">Life Expectancy Category [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_LifeExpectancyCategoryAxis" xlink:to="lab_hmh_LifeExpectancyCategoryAxis" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_LifeExpectancyCategoryDomain" xlink:label="loc_hmh_LifeExpectancyCategoryDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_LifeExpectancyCategoryDomain" xml:lang="en-US">Life Expectancy Category [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_LifeExpectancyCategoryDomain" xlink:to="lab_hmh_LifeExpectancyCategoryDomain" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_MalePensionersMember" xlink:label="loc_hmh_MalePensionersMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_MalePensionersMember" xml:lang="en-US">Male Pensioners [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_MalePensionersMember" xlink:to="lab_hmh_MalePensionersMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_FemalePensionersMember" xlink:label="loc_hmh_FemalePensionersMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_FemalePensionersMember" xml:lang="en-US">Female Pensioners [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_FemalePensionersMember" xlink:to="lab_hmh_FemalePensionersMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DefinedBenefitPlanCurrentLifeExpectancyAfterRetirement" xlink:label="loc_hmh_DefinedBenefitPlanCurrentLifeExpectancyAfterRetirement" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DefinedBenefitPlanCurrentLifeExpectancyAfterRetirement" xml:lang="en-US">Defined Benefit Plan Current Life Expectancy After Retirement</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_DefinedBenefitPlanCurrentLifeExpectancyAfterRetirement" xml:lang="en-US">Defined benefit plan current life expectancy after retirement</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DefinedBenefitPlanCurrentLifeExpectancyAfterRetirement" xlink:to="lab_hmh_DefinedBenefitPlanCurrentLifeExpectancyAfterRetirement" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DefinedBenefitPlanCurrentLifeExpectancyAfterRetirement" xml:lang="en-US">Defined benefit plan current life expectancy after retirement.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeLossAfterTaxAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeLossAfterTaxAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeLossAfterTaxAbstract" xml:lang="en-US">Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeLossAfterTaxAbstract" xlink:to="lab_us-gaap_DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeLossAfterTaxAbstract" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_EffectOfOnePercentagePointDefinedBenefitObligationTable" xlink:label="loc_hmh_EffectOfOnePercentagePointDefinedBenefitObligationTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_EffectOfOnePercentagePointDefinedBenefitObligationTable" xml:lang="en-US">Effect Of One Percentage Point Defined Benefit Obligation [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_EffectOfOnePercentagePointDefinedBenefitObligationTable" xlink:to="lab_hmh_EffectOfOnePercentagePointDefinedBenefitObligationTable" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ActuarialAssumptionTypeAxis" xlink:label="loc_hmh_ActuarialAssumptionTypeAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ActuarialAssumptionTypeAxis" xml:lang="en-US">Actuarial Assumption Type [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ActuarialAssumptionTypeAxis" xlink:to="lab_hmh_ActuarialAssumptionTypeAxis" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ActuarialAssumptionTypeDomain" xlink:label="loc_hmh_ActuarialAssumptionTypeDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ActuarialAssumptionTypeDomain" xml:lang="en-US">Actuarial Assumption Type [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ActuarialAssumptionTypeDomain" xlink:to="lab_hmh_ActuarialAssumptionTypeDomain" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DiscountRateMember" xlink:label="loc_hmh_DiscountRateMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DiscountRateMember" xml:lang="en-US">Discount Rate [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DiscountRateMember" xlink:to="lab_hmh_DiscountRateMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_FutureSalaryGrowthMember" xlink:label="loc_hmh_FutureSalaryGrowthMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_FutureSalaryGrowthMember" xml:lang="en-US">Future Salary Growth [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_FutureSalaryGrowthMember" xlink:to="lab_hmh_FutureSalaryGrowthMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_EffectOfOnePercentagePointDefinedBenefitObligationLineItems" xlink:label="loc_hmh_EffectOfOnePercentagePointDefinedBenefitObligationLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_EffectOfOnePercentagePointDefinedBenefitObligationLineItems" xml:lang="en-US">Effect Of One Percentage Point Defined Benefit Obligation [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_EffectOfOnePercentagePointDefinedBenefitObligationLineItems" xlink:to="lab_hmh_EffectOfOnePercentagePointDefinedBenefitObligationLineItems" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ActuarialAssumptionSensitivityEffectOnDefinedBenefitObligationAmount" xlink:label="loc_hmh_ActuarialAssumptionSensitivityEffectOnDefinedBenefitObligationAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ActuarialAssumptionSensitivityEffectOnDefinedBenefitObligationAmount" xml:lang="en-US">Actuarial Assumption Sensitivity Effect On Defined Benefit Obligation Amount</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ActuarialAssumptionSensitivityEffectOnDefinedBenefitObligationAmount" xlink:to="lab_hmh_ActuarialAssumptionSensitivityEffectOnDefinedBenefitObligationAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ActuarialAssumptionSensitivityEffectOnDefinedBenefitObligationAmount" xml:lang="en-US">Actuarial assumption sensitivity effect on defined benefit obligation amount.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_SensitivityDirectionAxis" xlink:label="loc_hmh_SensitivityDirectionAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_SensitivityDirectionAxis" xml:lang="en-US">Sensitivity Direction [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_SensitivityDirectionAxis" xlink:to="lab_hmh_SensitivityDirectionAxis" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_SensitivityDirectionDomain" xlink:label="loc_hmh_SensitivityDirectionDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_SensitivityDirectionDomain" xml:lang="en-US">Sensitivity Direction [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_SensitivityDirectionDomain" xlink:to="lab_hmh_SensitivityDirectionDomain" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_IncreaseMember" xlink:label="loc_hmh_IncreaseMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_IncreaseMember" xml:lang="en-US">Increase [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_IncreaseMember" xlink:to="lab_hmh_IncreaseMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DecreaseMember" xlink:label="loc_hmh_DecreaseMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DecreaseMember" xml:lang="en-US">Decrease [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DecreaseMember" xlink:to="lab_hmh_DecreaseMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanExpectedAmountsAbstract" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedAmountsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedAmountsAbstract" xml:lang="en-US">Defined Benefit Plan, Expected Amounts [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedAmountsAbstract" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedAmountsAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year One</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year Two</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year Three</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year Four</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, Year Five</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter" xlink:label="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter" xml:lang="en-US">Defined Benefit Plan, Expected Future Benefit Payment, after Year Five for Next Five Years</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter" xlink:to="lab_us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ActuarialAssumptionChangeRatePercentage" xlink:label="loc_hmh_ActuarialAssumptionChangeRatePercentage" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ActuarialAssumptionChangeRatePercentage" xml:lang="en-US">Actuarial Assumption Change Rate Percentage</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ActuarialAssumptionChangeRatePercentage" xlink:to="lab_hmh_ActuarialAssumptionChangeRatePercentage" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ActuarialAssumptionChangeRatePercentage" xml:lang="en-US">Actuarial assumption change rate percentage.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedContributionPlanNumberOfEmployees" xlink:label="loc_us-gaap_DefinedContributionPlanNumberOfEmployees" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedContributionPlanNumberOfEmployees" xml:lang="en-US">Defined Contribution Plan, Number of Employees</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedContributionPlanNumberOfEmployees" xlink:to="lab_us-gaap_DefinedContributionPlanNumberOfEmployees" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DefinedContributionPlanCostRecognized" xlink:label="loc_us-gaap_DefinedContributionPlanCostRecognized" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DefinedContributionPlanCostRecognized" xml:lang="en-US">Defined Contribution Plan, Cost</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DefinedContributionPlanCostRecognized" xlink:to="lab_us-gaap_DefinedContributionPlanCostRecognized" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_TaxBenefitProvision" xlink:label="loc_hmh_TaxBenefitProvision" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_TaxBenefitProvision" xml:lang="en-US">Tax (Benefit) Provision</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_TaxBenefitProvision" xml:lang="en-US">Tax (benefit) provision</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_TaxBenefitProvision" xlink:to="lab_hmh_TaxBenefitProvision" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_TaxBenefitProvision" xml:lang="en-US">Tax (benefit) provision.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_EffectiveIncomeTaxRateReconciliationStockIssuanceCostsAmount" xlink:label="loc_hmh_EffectiveIncomeTaxRateReconciliationStockIssuanceCostsAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_EffectiveIncomeTaxRateReconciliationStockIssuanceCostsAmount" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Stock Issuance Costs, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_EffectiveIncomeTaxRateReconciliationStockIssuanceCostsAmount" xml:lang="en-US">IPO related transaction costs included in tax expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_EffectiveIncomeTaxRateReconciliationStockIssuanceCostsAmount" xlink:to="lab_hmh_EffectiveIncomeTaxRateReconciliationStockIssuanceCostsAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_EffectiveIncomeTaxRateReconciliationStockIssuanceCostsAmount" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Stock Issuance Costs, Amount</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiability" xlink:label="loc_hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiability" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiability" xml:lang="en-US">Adjustments To Additional Paid In Capital, Tax Receivable Agreement Liability</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiability" xml:lang="en-US">TRA liability</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiability" xlink:to="lab_hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiability" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiability" xml:lang="en-US">Adjustments To Additional Paid In Capital, Tax Receivable Agreement Liability</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AdjustmentsToAdditionalPaidInCapitalTaxImpactOfReorganization" xlink:label="loc_hmh_AdjustmentsToAdditionalPaidInCapitalTaxImpactOfReorganization" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AdjustmentsToAdditionalPaidInCapitalTaxImpactOfReorganization" xml:lang="en-US">Adjustments To Additional Paid In Capital, Tax Impact Of Reorganization</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_AdjustmentsToAdditionalPaidInCapitalTaxImpactOfReorganization" xml:lang="en-US">Tax impact of reorganization</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AdjustmentsToAdditionalPaidInCapitalTaxImpactOfReorganization" xlink:to="lab_hmh_AdjustmentsToAdditionalPaidInCapitalTaxImpactOfReorganization" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AdjustmentsToAdditionalPaidInCapitalTaxImpactOfReorganization" xml:lang="en-US">Adjustments To Additional Paid In Capital, Tax Impact Of Reorganization</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount" xlink:label="loc_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount" xml:lang="en-US">Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount" xlink:to="lab_us-gaap_ValuationAllowanceDeferredTaxAssetChangeInAmount" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AdditionInValuationAllowanceDeferredTaxAssetChangeInAmount" xlink:label="loc_hmh_AdditionInValuationAllowanceDeferredTaxAssetChangeInAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AdditionInValuationAllowanceDeferredTaxAssetChangeInAmount" xml:lang="en-US">Addition In Valuation Allowance Deferred Tax Asset Change In Amount</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AdditionInValuationAllowanceDeferredTaxAssetChangeInAmount" xlink:to="lab_hmh_AdditionInValuationAllowanceDeferredTaxAssetChangeInAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AdditionInValuationAllowanceDeferredTaxAssetChangeInAmount" xml:lang="en-US">Addition in valuation allowance deferred tax asset change in amount.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DeferredTaxAssetsValuationAllowanceReversal" xlink:label="loc_hmh_DeferredTaxAssetsValuationAllowanceReversal" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DeferredTaxAssetsValuationAllowanceReversal" xml:lang="en-US">Deferred Tax Assets Valuation Allowance Reversal</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DeferredTaxAssetsValuationAllowanceReversal" xlink:to="lab_hmh_DeferredTaxAssetsValuationAllowanceReversal" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DeferredTaxAssetsValuationAllowanceReversal" xml:lang="en-US">Deferred tax assets valuation allowance reversal.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DeferredTaxAssetsOperatingLossReductionInCarryforwards" xlink:label="loc_hmh_DeferredTaxAssetsOperatingLossReductionInCarryforwards" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DeferredTaxAssetsOperatingLossReductionInCarryforwards" xml:lang="en-US">Deferred Tax Assets Operating Loss Reduction In Carryforwards</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DeferredTaxAssetsOperatingLossReductionInCarryforwards" xlink:to="lab_hmh_DeferredTaxAssetsOperatingLossReductionInCarryforwards" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DeferredTaxAssetsOperatingLossReductionInCarryforwards" xml:lang="en-US">Deferred tax assets operating loss reduction in carryforwards.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ForeignCurrencyTranslationAdjustments" xlink:label="loc_hmh_ForeignCurrencyTranslationAdjustments" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ForeignCurrencyTranslationAdjustments" xml:lang="en-US">Foreign Currency Translation Adjustments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ForeignCurrencyTranslationAdjustments" xlink:to="lab_hmh_ForeignCurrencyTranslationAdjustments" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ForeignCurrencyTranslationAdjustments" xml:lang="en-US">Foreign currency translation adjustments.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AdditionInValuationAllowanceDeferedTaxAssets" xlink:label="loc_hmh_AdditionInValuationAllowanceDeferedTaxAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AdditionInValuationAllowanceDeferedTaxAssets" xml:lang="en-US">Addition In Valuation Allowance Defered Tax Assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AdditionInValuationAllowanceDeferedTaxAssets" xlink:to="lab_hmh_AdditionInValuationAllowanceDeferedTaxAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AdditionInValuationAllowanceDeferedTaxAssets" xml:lang="en-US">Addition in valuation allowance defered tax assets .</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DeferredTaxAssetsInterestCarryforwardSubjectToExpiration" xlink:label="loc_hmh_DeferredTaxAssetsInterestCarryforwardSubjectToExpiration" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DeferredTaxAssetsInterestCarryforwardSubjectToExpiration" xml:lang="en-US">Deferred Tax Assets Interest Carryforward Subject To Expiration</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DeferredTaxAssetsInterestCarryforwardSubjectToExpiration" xlink:to="lab_hmh_DeferredTaxAssetsInterestCarryforwardSubjectToExpiration" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DeferredTaxAssetsInterestCarryforwardSubjectToExpiration" xml:lang="en-US">Deferred tax assets interest carryforward subject to expiration.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_UnrecognizedTaxBenefitsFavorableRateAmount" xlink:label="loc_hmh_UnrecognizedTaxBenefitsFavorableRateAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_UnrecognizedTaxBenefitsFavorableRateAmount" xml:lang="en-US">Unrecognized Tax Benefits Favorable Rate Amount</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_UnrecognizedTaxBenefitsFavorableRateAmount" xlink:to="lab_hmh_UnrecognizedTaxBenefitsFavorableRateAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_UnrecognizedTaxBenefitsFavorableRateAmount" xml:lang="en-US">Unrecognized tax benefits favorable rate amount.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxAssetsOperatingLossCarryforwards" xlink:label="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards" xml:lang="en-US">Deferred Tax Assets, Operating Loss Carryforwards</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards" xml:lang="en-US">Net operating loss carryforwards</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards" xlink:to="lab_us-gaap_DeferredTaxAssetsOperatingLossCarryforwards" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpiration" xlink:label="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpiration" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpiration" xml:lang="en-US">Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpiration" xlink:to="lab_us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsSubjectToExpiration" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxAssetInterestCarryforward" xlink:label="loc_us-gaap_DeferredTaxAssetInterestCarryforward" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredTaxAssetInterestCarryforward" xml:lang="en-US">Deferred Tax Asset, Interest Carryforward</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredTaxAssetInterestCarryforward" xml:lang="en-US">Interest carryforwards</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetInterestCarryforward" xlink:to="lab_us-gaap_DeferredTaxAssetInterestCarryforward" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UndistributedEarningsOfForeignSubsidiaries" xlink:label="loc_us-gaap_UndistributedEarningsOfForeignSubsidiaries" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_UndistributedEarningsOfForeignSubsidiaries" xml:lang="en-US">Undistributed Earnings of Foreign Subsidiaries</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UndistributedEarningsOfForeignSubsidiaries" xlink:to="lab_us-gaap_UndistributedEarningsOfForeignSubsidiaries" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrecognizedTaxBenefits" xlink:label="loc_us-gaap_UnrecognizedTaxBenefits" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_UnrecognizedTaxBenefits" xml:lang="en-US">Unrecognized Tax Benefits</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_UnrecognizedTaxBenefits" xml:lang="en-US">Balance as of January&#160;1,</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_UnrecognizedTaxBenefits" xml:lang="en-US">Balance as of December&#160;31,</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefits" xlink:to="lab_us-gaap_UnrecognizedTaxBenefits" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense" xlink:label="loc_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense" xml:lang="en-US">Income Tax Examination, Penalties and Interest Expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense" xlink:to="lab_us-gaap_IncomeTaxExaminationPenaltiesAndInterestExpense" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense" xml:lang="en-US">Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense" xlink:to="lab_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RegulatoryAssetAxis" xlink:label="loc_us-gaap_RegulatoryAssetAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RegulatoryAssetAxis" xml:lang="en-US">Regulatory Asset [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RegulatoryAssetAxis" xlink:to="lab_us-gaap_RegulatoryAssetAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RegulatoryAssetDomain" xlink:label="loc_us-gaap_RegulatoryAssetDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RegulatoryAssetDomain" xml:lang="en-US">Regulatory Asset [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RegulatoryAssetDomain" xlink:to="lab_us-gaap_RegulatoryAssetDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxChargesMember" xlink:label="loc_us-gaap_DeferredIncomeTaxChargesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredIncomeTaxChargesMember" xml:lang="en-US">Deferred Income Tax Charge [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredIncomeTaxChargesMember" xlink:to="lab_us-gaap_DeferredIncomeTaxChargesMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CurrentFederalStateAndLocalTaxExpenseBenefitAbstract" xlink:label="loc_us-gaap_CurrentFederalStateAndLocalTaxExpenseBenefitAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CurrentFederalStateAndLocalTaxExpenseBenefitAbstract" xml:lang="en-US">Current Federal, State and Local, Tax Expense (Benefit) [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CurrentFederalStateAndLocalTaxExpenseBenefitAbstract" xml:lang="en-US">Current:</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CurrentFederalStateAndLocalTaxExpenseBenefitAbstract" xlink:to="lab_us-gaap_CurrentFederalStateAndLocalTaxExpenseBenefitAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CurrentStateAndLocalTaxExpenseBenefit" xlink:label="loc_us-gaap_CurrentStateAndLocalTaxExpenseBenefit" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CurrentStateAndLocalTaxExpenseBenefit" xml:lang="en-US">Current State and Local Tax Expense (Benefit)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CurrentStateAndLocalTaxExpenseBenefit" xml:lang="en-US">Domestic</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CurrentStateAndLocalTaxExpenseBenefit" xlink:to="lab_us-gaap_CurrentStateAndLocalTaxExpenseBenefit" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CurrentForeignTaxExpenseBenefit" xlink:label="loc_us-gaap_CurrentForeignTaxExpenseBenefit" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CurrentForeignTaxExpenseBenefit" xml:lang="en-US">Current Foreign Tax Expense (Benefit)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_CurrentForeignTaxExpenseBenefit" xml:lang="en-US">Foreign</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CurrentForeignTaxExpenseBenefit" xlink:to="lab_us-gaap_CurrentForeignTaxExpenseBenefit" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_CurrentIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_CurrentIncomeTaxExpenseBenefit" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_CurrentIncomeTaxExpenseBenefit" xml:lang="en-US">Current Income Tax Expense (Benefit)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:label="lab_us-gaap_CurrentIncomeTaxExpenseBenefit" xml:lang="en-US">Total current tax expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CurrentIncomeTaxExpenseBenefit" xlink:to="lab_us-gaap_CurrentIncomeTaxExpenseBenefit" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredFederalStateAndLocalTaxExpenseBenefitAbstract" xlink:label="loc_us-gaap_DeferredFederalStateAndLocalTaxExpenseBenefitAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredFederalStateAndLocalTaxExpenseBenefitAbstract" xml:lang="en-US">Deferred Federal, State and Local, Tax Expense (Benefit) [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredFederalStateAndLocalTaxExpenseBenefitAbstract" xml:lang="en-US">Deferred:</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredFederalStateAndLocalTaxExpenseBenefitAbstract" xlink:to="lab_us-gaap_DeferredFederalStateAndLocalTaxExpenseBenefitAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit" xml:lang="en-US">Deferred State and Local Income Tax Expense (Benefit)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit" xml:lang="en-US">Domestic</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit" xlink:to="lab_us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredForeignIncomeTaxExpenseBenefit" xlink:label="loc_us-gaap_DeferredForeignIncomeTaxExpenseBenefit" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredForeignIncomeTaxExpenseBenefit" xml:lang="en-US">Deferred Foreign Income Tax Expense (Benefit)</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredForeignIncomeTaxExpenseBenefit" xml:lang="en-US">Foreign</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredForeignIncomeTaxExpenseBenefit" xlink:to="lab_us-gaap_DeferredForeignIncomeTaxExpenseBenefit" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic" xml:lang="en-US">Income (Loss) from Continuing Operations before Income Taxes, Domestic</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic" xml:lang="en-US">Domestic</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic" xlink:to="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign" xlink:label="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign" xml:lang="en-US">Income (Loss) from Continuing Operations before Income Taxes, Foreign</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign" xml:lang="en-US">Foreign</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign" xlink:to="lab_us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationTable" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationTable" xml:lang="en-US">Effective Income Tax Rate Reconciliation [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationTable" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationLineItems" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationLineItems" xml:lang="en-US">Effective Income Tax Rate Reconciliation [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationLineItems" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" xlink:label="loc_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" xml:lang="en-US">Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" xml:lang="en-US">Statutory income tax rate (25.8%)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" xlink:to="lab_us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationCrossBorderTaxEffectAmount" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationCrossBorderTaxEffectAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationCrossBorderTaxEffectAmount" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Cross-Border Tax Effect, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationCrossBorderTaxEffectAmount" xml:lang="en-US">Difference between local income tax rate and Dutch income tax rate</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationCrossBorderTaxEffectAmount" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationCrossBorderTaxEffectAmount" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationNondeductibleExpense" xlink:label="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpense" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeTaxReconciliationNondeductibleExpense" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Nondeductible Expense, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncomeTaxReconciliationNondeductibleExpense" xml:lang="en-US">Nondeductible expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxReconciliationNondeductibleExpense" xlink:to="lab_us-gaap_IncomeTaxReconciliationNondeductibleExpense" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_EffectiveIncomeTaxRateReconciliationUnrecognizedTaxBenefitsAmount" xlink:label="loc_hmh_EffectiveIncomeTaxRateReconciliationUnrecognizedTaxBenefitsAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_EffectiveIncomeTaxRateReconciliationUnrecognizedTaxBenefitsAmount" xml:lang="en-US">Effective Income Tax Rate Reconciliation Unrecognized Tax Benefits Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_EffectiveIncomeTaxRateReconciliationUnrecognizedTaxBenefitsAmount" xml:lang="en-US">Unrecognized tax benefits</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_EffectiveIncomeTaxRateReconciliationUnrecognizedTaxBenefitsAmount" xlink:to="lab_hmh_EffectiveIncomeTaxRateReconciliationUnrecognizedTaxBenefitsAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_EffectiveIncomeTaxRateReconciliationUnrecognizedTaxBenefitsAmount" xml:lang="en-US">Effective income tax rate reconciliation unrecognized tax benefits amount.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationTaxCredits" xlink:label="loc_us-gaap_IncomeTaxReconciliationTaxCredits" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeTaxReconciliationTaxCredits" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Tax Credit, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncomeTaxReconciliationTaxCredits" xml:lang="en-US">Income taxed to U.S. shareholders</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxReconciliationTaxCredits" xlink:to="lab_us-gaap_IncomeTaxReconciliationTaxCredits" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Tax Expense (Benefit), Share-Based Payment Arrangement, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount" xml:lang="en-US">Shareholder tax benefit</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance" xlink:label="loc_us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance" xml:lang="en-US">Change in valuation allowance</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance" xlink:to="lab_us-gaap_IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationChangeInEnactedTaxRate" xlink:label="loc_us-gaap_IncomeTaxReconciliationChangeInEnactedTaxRate" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeTaxReconciliationChangeInEnactedTaxRate" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncomeTaxReconciliationChangeInEnactedTaxRate" xml:lang="en-US">Change in tax rate</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxReconciliationChangeInEnactedTaxRate" xlink:to="lab_us-gaap_IncomeTaxReconciliationChangeInEnactedTaxRate" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_EffectiveIncomeTaxRateReconciliationWithholdingTaxesAmount" xlink:label="loc_hmh_EffectiveIncomeTaxRateReconciliationWithholdingTaxesAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_EffectiveIncomeTaxRateReconciliationWithholdingTaxesAmount" xml:lang="en-US">Effective Income Tax Rate Reconciliation Withholding Taxes Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_EffectiveIncomeTaxRateReconciliationWithholdingTaxesAmount" xml:lang="en-US">Withholding taxes</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_EffectiveIncomeTaxRateReconciliationWithholdingTaxesAmount" xlink:to="lab_hmh_EffectiveIncomeTaxRateReconciliationWithholdingTaxesAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_EffectiveIncomeTaxRateReconciliationWithholdingTaxesAmount" xml:lang="en-US">Effective income tax rate reconciliation withholding taxes amount.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IncomeTaxReconciliationOtherReconcilingItems" xlink:label="loc_us-gaap_IncomeTaxReconciliationOtherReconcilingItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IncomeTaxReconciliationOtherReconcilingItems" xml:lang="en-US">Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IncomeTaxReconciliationOtherReconcilingItems" xml:lang="en-US">Other</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxReconciliationOtherReconcilingItems" xlink:to="lab_us-gaap_IncomeTaxReconciliationOtherReconcilingItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComponentsOfDeferredTaxAssetsAbstract" xlink:label="loc_us-gaap_ComponentsOfDeferredTaxAssetsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ComponentsOfDeferredTaxAssetsAbstract" xml:lang="en-US">Components of Deferred Tax Assets [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ComponentsOfDeferredTaxAssetsAbstract" xml:lang="en-US">Deferred tax assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComponentsOfDeferredTaxAssetsAbstract" xlink:to="lab_us-gaap_ComponentsOfDeferredTaxAssetsAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits" xlink:label="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits" xml:lang="en-US">Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Benefits</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits" xml:lang="en-US">Employee benefit plan liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits" xlink:to="lab_us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsEmployeeBenefits" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment" xlink:label="loc_us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment" xml:lang="en-US">Deferred Tax Assets, Property, Plant and Equipment</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment" xml:lang="en-US">Property, plant and equipment</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment" xlink:to="lab_us-gaap_DeferredTaxAssetsPropertyPlantAndEquipment" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DeferredTaxAssetsProvisions" xlink:label="loc_hmh_DeferredTaxAssetsProvisions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DeferredTaxAssetsProvisions" xml:lang="en-US">Deferred Tax Assets Provisions</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_DeferredTaxAssetsProvisions" xml:lang="en-US">Provisions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DeferredTaxAssetsProvisions" xlink:to="lab_hmh_DeferredTaxAssetsProvisions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DeferredTaxAssetsProvisions" xml:lang="en-US">Deferred tax assets provisions.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxAssetsInventory" xlink:label="loc_us-gaap_DeferredTaxAssetsInventory" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredTaxAssetsInventory" xml:lang="en-US">Deferred Tax Assets, Inventory</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredTaxAssetsInventory" xml:lang="en-US">Inventories</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsInventory" xlink:to="lab_us-gaap_DeferredTaxAssetsInventory" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxAssetsOther" xlink:label="loc_us-gaap_DeferredTaxAssetsOther" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredTaxAssetsOther" xml:lang="en-US">Deferred Tax Assets, Other</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_DeferredTaxAssetsOther" xml:lang="en-US">Other</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsOther" xlink:to="lab_us-gaap_DeferredTaxAssetsOther" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxAssetsGross" xlink:label="loc_us-gaap_DeferredTaxAssetsGross" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredTaxAssetsGross" xml:lang="en-US">Deferred Tax Assets, Gross</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="lab_us-gaap_DeferredTaxAssetsGross" xml:lang="en-US">Total deferred tax asset</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsGross" xlink:to="lab_us-gaap_DeferredTaxAssetsGross" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxAssetsValuationAllowance" xlink:label="loc_us-gaap_DeferredTaxAssetsValuationAllowance" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredTaxAssetsValuationAllowance" xml:lang="en-US">Deferred Tax Assets, Valuation Allowance</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_DeferredTaxAssetsValuationAllowance" xml:lang="en-US">Valuation allowance</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxAssetsValuationAllowance" xlink:to="lab_us-gaap_DeferredTaxAssetsValuationAllowance" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ComponentsOfDeferredTaxLiabilitiesAbstract" xlink:label="loc_us-gaap_ComponentsOfDeferredTaxLiabilitiesAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ComponentsOfDeferredTaxLiabilitiesAbstract" xml:lang="en-US">Components of Deferred Tax Liabilities [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ComponentsOfDeferredTaxLiabilitiesAbstract" xml:lang="en-US">Deferred tax liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ComponentsOfDeferredTaxLiabilitiesAbstract" xlink:to="lab_us-gaap_ComponentsOfDeferredTaxLiabilitiesAbstract" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DeferredTaxLiabilitiesCustomerRelationships" xlink:label="loc_hmh_DeferredTaxLiabilitiesCustomerRelationships" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DeferredTaxLiabilitiesCustomerRelationships" xml:lang="en-US">Deferred Tax Liabilities Customer Relationships</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_hmh_DeferredTaxLiabilitiesCustomerRelationships" xml:lang="en-US">Customer relationships</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DeferredTaxLiabilitiesCustomerRelationships" xlink:to="lab_hmh_DeferredTaxLiabilitiesCustomerRelationships" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DeferredTaxLiabilitiesCustomerRelationships" xml:lang="en-US">Deferred tax liabilities customer relationships.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets" xml:lang="en-US">Deferred Tax Liabilities, Intangible Assets</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets" xml:lang="en-US">Other intangible assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets" xlink:to="lab_us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_DeferredTaxLiabilitiesContractAssets" xlink:label="loc_hmh_DeferredTaxLiabilitiesContractAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_DeferredTaxLiabilitiesContractAssets" xml:lang="en-US">Deferred Tax Liabilities Contract Assets</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_hmh_DeferredTaxLiabilitiesContractAssets" xml:lang="en-US">Contract assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_DeferredTaxLiabilitiesContractAssets" xlink:to="lab_hmh_DeferredTaxLiabilitiesContractAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_DeferredTaxLiabilitiesContractAssets" xml:lang="en-US">Deferred tax liabilities contract assets.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxLiabilitiesDerivatives" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesDerivatives" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesDerivatives" xml:lang="en-US">Deferred Tax Liabilities, Derivatives</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesDerivatives" xml:lang="en-US">Derivative financial instruments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxLiabilitiesDerivatives" xlink:to="lab_us-gaap_DeferredTaxLiabilitiesDerivatives" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredTaxLiabilitiesOther" xlink:label="loc_us-gaap_DeferredTaxLiabilitiesOther" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesOther" xml:lang="en-US">Deferred Tax Liabilities, Other</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="lab_us-gaap_DeferredTaxLiabilitiesOther" xml:lang="en-US">Other</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredTaxLiabilitiesOther" xlink:to="lab_us-gaap_DeferredTaxLiabilitiesOther" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DeferredIncomeTaxLiabilities" xlink:label="loc_us-gaap_DeferredIncomeTaxLiabilities" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DeferredIncomeTaxLiabilities" xml:lang="en-US">Deferred Tax Liabilities, Gross</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTotalLabel" xlink:label="lab_us-gaap_DeferredIncomeTaxLiabilities" xml:lang="en-US">Total deferred tax liabilities</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DeferredIncomeTaxLiabilities" xlink:to="lab_us-gaap_DeferredIncomeTaxLiabilities" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_NetDeferredTaxLiabilityAsset" xlink:label="loc_hmh_NetDeferredTaxLiabilityAsset" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_NetDeferredTaxLiabilityAsset" xml:lang="en-US">Net Deferred Tax (Liability) Asset</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_NetDeferredTaxLiabilityAsset" xml:lang="en-US">Net deferred tax (liability) asset</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_NetDeferredTaxLiabilityAsset" xlink:to="lab_hmh_NetDeferredTaxLiabilityAsset" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_NetDeferredTaxLiabilityAsset" xml:lang="en-US">Net deferred tax (liability) asset.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions" xml:lang="en-US">Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions" xml:lang="en-US">Increases in unrecognized tax benefits - current year positions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions" xlink:to="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions" xml:lang="en-US">Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions" xml:lang="en-US">Increases in unrecognized tax benefits - prior year positions</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions" xlink:to="lab_us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xml:lang="en-US">Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:to="lab_us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_StatementGeographicalAxis" xlink:label="loc_srt_StatementGeographicalAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_StatementGeographicalAxis" xml:lang="en-US">Geographical [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_StatementGeographicalAxis" xml:lang="en-US">Geographical [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_StatementGeographicalAxis" xlink:to="lab_srt_StatementGeographicalAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_SegmentGeographicalDomain" xlink:label="loc_srt_SegmentGeographicalDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_SegmentGeographicalDomain" xml:lang="en-US">Geographical [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_SegmentGeographicalDomain" xml:lang="en-US">Geographical [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_SegmentGeographicalDomain" xlink:to="lab_srt_SegmentGeographicalDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_NO" xlink:label="loc_country_NO" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_country_NO" xml:lang="en-US">NORWAY</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_country_NO" xml:lang="en-US">Norway</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_NO" xlink:to="lab_country_NO" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_MX" xlink:label="loc_country_MX" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_country_MX" xml:lang="en-US">MEXICO</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_country_MX" xml:lang="en-US">Mexico</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_MX" xlink:to="lab_country_MX" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_DE" xlink:label="loc_country_DE" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_country_DE" xml:lang="en-US">GERMANY</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_country_DE" xml:lang="en-US">Germany</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_DE" xlink:to="lab_country_DE" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsByNatureAxis" xlink:label="loc_us-gaap_GuaranteeObligationsByNatureAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GuaranteeObligationsByNatureAxis" xml:lang="en-US">Guarantor Obligations, Nature [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_GuaranteeObligationsByNatureAxis" xml:lang="en-US">Guarantor Obligations, Nature [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GuaranteeObligationsByNatureAxis" xlink:to="lab_us-gaap_GuaranteeObligationsByNatureAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsNatureDomain" xlink:label="loc_us-gaap_GuaranteeObligationsNatureDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GuaranteeObligationsNatureDomain" xml:lang="en-US">Guarantor Obligations, Nature [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_GuaranteeObligationsNatureDomain" xml:lang="en-US">Guarantor Obligations, Nature [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GuaranteeObligationsNatureDomain" xlink:to="lab_us-gaap_GuaranteeObligationsNatureDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancialGuaranteeMember" xlink:label="loc_us-gaap_FinancialGuaranteeMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FinancialGuaranteeMember" xml:lang="en-US">Financial Guarantee [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_FinancialGuaranteeMember" xml:lang="en-US">Bank guarantee</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancialGuaranteeMember" xlink:to="lab_us-gaap_FinancialGuaranteeMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated" xlink:label="loc_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated" xml:lang="en-US">Restructuring and Related Cost, Number of Positions Eliminated</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated" xml:lang="en-US">Number of employees impacted by restructuring plan</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated" xlink:to="lab_us-gaap_RestructuringAndRelatedCostNumberOfPositionsEliminated" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingLeaseImpairmentLoss" xlink:label="loc_us-gaap_OperatingLeaseImpairmentLoss" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingLeaseImpairmentLoss" xml:lang="en-US">Operating Lease, Impairment Loss</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OperatingLeaseImpairmentLoss" xml:lang="en-US">Impairment of right-of-use assets</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingLeaseImpairmentLoss" xlink:to="lab_us-gaap_OperatingLeaseImpairmentLoss" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GuaranteeObligationsCurrentCarryingValue" xlink:label="loc_us-gaap_GuaranteeObligationsCurrentCarryingValue" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GuaranteeObligationsCurrentCarryingValue" xml:lang="en-US">Guarantor Obligations, Current Carrying Value</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_GuaranteeObligationsCurrentCarryingValue" xml:lang="en-US">Outstanding bank guarantees</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GuaranteeObligationsCurrentCarryingValue" xlink:to="lab_us-gaap_GuaranteeObligationsCurrentCarryingValue" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted" xlink:label="loc_us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted" xml:lang="en-US">Purchase Commitment, Remaining Minimum Amount Committed</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted" xml:lang="en-US">Purchase commitments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted" xlink:to="lab_us-gaap_PurchaseCommitmentRemainingMinimumAmountCommitted" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_RestructuringAndOtherExpenses" xlink:label="loc_hmh_RestructuringAndOtherExpenses" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_RestructuringAndOtherExpenses" xml:lang="en-US">Restructuring And Other Expenses</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_RestructuringAndOtherExpenses" xml:lang="en-US">Restructuring and other expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_RestructuringAndOtherExpenses" xlink:to="lab_hmh_RestructuringAndOtherExpenses" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_RestructuringAndOtherExpenses" xml:lang="en-US">Restructuring and other expenses.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringReserve" xlink:label="loc_us-gaap_RestructuringReserve" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RestructuringReserve" xml:lang="en-US">Restructuring Reserve</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="lab_us-gaap_RestructuringReserve" xml:lang="en-US">Balance at the beginning of the period</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="lab_us-gaap_RestructuringReserve" xml:lang="en-US">Balance at the end of the period</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringReserve" xlink:to="lab_us-gaap_RestructuringReserve" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringCharges" xlink:label="loc_us-gaap_RestructuringCharges" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RestructuringCharges" xml:lang="en-US">Restructuring Charges</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RestructuringCharges" xml:lang="en-US">Restructuring and other expenses</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringCharges" xlink:to="lab_us-gaap_RestructuringCharges" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PaymentsForRestructuring" xlink:label="loc_us-gaap_PaymentsForRestructuring" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PaymentsForRestructuring" xml:lang="en-US">Payments for Restructuring</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_PaymentsForRestructuring" xml:lang="en-US">Reductions for payments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsForRestructuring" xlink:to="lab_us-gaap_PaymentsForRestructuring" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RestructuringReserveTranslationAndOtherAdjustment" xlink:label="loc_us-gaap_RestructuringReserveTranslationAndOtherAdjustment" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RestructuringReserveTranslationAndOtherAdjustment" xml:lang="en-US">Restructuring Reserve, Translation and Other Adjustment</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_RestructuringReserveTranslationAndOtherAdjustment" xml:lang="en-US">Foreign currency translation</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RestructuringReserveTranslationAndOtherAdjustment" xlink:to="lab_us-gaap_RestructuringReserveTranslationAndOtherAdjustment" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OtherBakerHugesCompaniesMember" xlink:label="loc_hmh_OtherBakerHugesCompaniesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OtherBakerHugesCompaniesMember" xml:lang="en-US">Other Baker Huges Companies [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_OtherBakerHugesCompaniesMember" xml:lang="en-US">Other Baker Hughes companies</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OtherBakerHugesCompaniesMember" xlink:to="lab_hmh_OtherBakerHugesCompaniesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_OtherBakerHugesCompaniesMember" xml:lang="en-US">Other Baker Huges Companies</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OtherAkastorCompaniesMember" xlink:label="loc_hmh_OtherAkastorCompaniesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OtherAkastorCompaniesMember" xml:lang="en-US">Other Akastor Companies [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_OtherAkastorCompaniesMember" xml:lang="en-US">Other Akastor companies</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OtherAkastorCompaniesMember" xlink:to="lab_hmh_OtherAkastorCompaniesMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_OtherAkastorCompaniesMember" xml:lang="en-US">Other Akastor Companies</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_TanajibHoldingCompanyMember" xlink:label="loc_hmh_TanajibHoldingCompanyMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_TanajibHoldingCompanyMember" xml:lang="en-US">Tanajib Holding Company [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_TanajibHoldingCompanyMember" xml:lang="en-US">Tanajib Holding Company</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_TanajibHoldingCompanyMember" xlink:to="lab_hmh_TanajibHoldingCompanyMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_TanajibHoldingCompanyMember" xml:lang="en-US">Tanajib Holding Company</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCredit" xlink:label="loc_us-gaap_LineOfCredit" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LineOfCredit" xml:lang="en-US">Long-Term Line of Credit</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LineOfCredit" xlink:to="lab_us-gaap_LineOfCredit" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd" xlink:label="loc_us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd" xml:lang="en-US">Line of Credit Facility, Interest Rate at Period End</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd" xlink:to="lab_us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_LineOfCreditFacilityPeriodicPayment" xlink:label="loc_us-gaap_LineOfCreditFacilityPeriodicPayment" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_LineOfCreditFacilityPeriodicPayment" xml:lang="en-US">Line of Credit Facility, Periodic Payment</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LineOfCreditFacilityPeriodicPayment" xlink:to="lab_us-gaap_LineOfCreditFacilityPeriodicPayment" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_ProceedsFromTheLiquidation" xlink:label="loc_hmh_ProceedsFromTheLiquidation" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_ProceedsFromTheLiquidation" xml:lang="en-US">Proceeds From The Liquidation</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_ProceedsFromTheLiquidation" xlink:to="lab_hmh_ProceedsFromTheLiquidation" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_ProceedsFromTheLiquidation" xml:lang="en-US">Proceeds from the liquidation.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AmountOfUnpaidPensionCost" xlink:label="loc_hmh_AmountOfUnpaidPensionCost" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AmountOfUnpaidPensionCost" xml:lang="en-US">Amount Of Unpaid Pension Cost</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AmountOfUnpaidPensionCost" xlink:to="lab_hmh_AmountOfUnpaidPensionCost" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AmountOfUnpaidPensionCost" xml:lang="en-US">Amount of unpaid pension cost.</link:label>
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_AmountReceivableFromPensionPaymentsFormSubsidiary" xlink:label="loc_hmh_AmountReceivableFromPensionPaymentsFormSubsidiary" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_AmountReceivableFromPensionPaymentsFormSubsidiary" xml:lang="en-US">Amount Receivable From Pension Payments Form Subsidiary</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_AmountReceivableFromPensionPaymentsFormSubsidiary" xlink:to="lab_hmh_AmountReceivableFromPensionPaymentsFormSubsidiary" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_AmountReceivableFromPensionPaymentsFormSubsidiary" xml:lang="en-US">Amount receivable from pension payments form subsidiary.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_PensionCostsMember" xlink:label="loc_us-gaap_PensionCostsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_PensionCostsMember" xml:lang="en-US">Pension Costs [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PensionCostsMember" xlink:to="lab_us-gaap_PensionCostsMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NumberOfOperatingSegments" xlink:label="loc_us-gaap_NumberOfOperatingSegments" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NumberOfOperatingSegments" xml:lang="en-US">Number of Operating Segments</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NumberOfOperatingSegments" xml:lang="en-US">Number of operating segments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NumberOfOperatingSegments" xlink:to="lab_us-gaap_NumberOfOperatingSegments" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_NumberOfReportableSegmentsNotDisclosedFlag" xlink:label="loc_hmh_NumberOfReportableSegmentsNotDisclosedFlag" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_NumberOfReportableSegmentsNotDisclosedFlag" xml:lang="en-US">Number Of Reportable Segments Not Disclosed Flag</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_NumberOfReportableSegmentsNotDisclosedFlag" xml:lang="en-US">Number of reportable segments not disclosed flag</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_NumberOfReportableSegmentsNotDisclosedFlag" xlink:to="lab_hmh_NumberOfReportableSegmentsNotDisclosedFlag" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_NumberOfReportableSegmentsNotDisclosedFlag" xml:lang="en-US">Number Of Reportable Segments Not Disclosed Flag.</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingExpenseInformationUsedByCodmDescription" xlink:label="loc_us-gaap_SegmentReportingExpenseInformationUsedByCodmDescription" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SegmentReportingExpenseInformationUsedByCodmDescription" xml:lang="en-US">Segment Reporting, Expense Information Used by CODM, Description</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingExpenseInformationUsedByCodmDescription" xlink:to="lab_us-gaap_SegmentReportingExpenseInformationUsedByCodmDescription" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration" xlink:label="loc_us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration" xml:lang="en-US">Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration" xlink:to="lab_us-gaap_SegmentReportingCodmIndividualTitleAndPositionOrGroupOrCommitteeNameExtensibleEnumeration" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingCodmProfitLossMeasureHowUsedDescription" xlink:label="loc_us-gaap_SegmentReportingCodmProfitLossMeasureHowUsedDescription" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SegmentReportingCodmProfitLossMeasureHowUsedDescription" xml:lang="en-US">Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingCodmProfitLossMeasureHowUsedDescription" xlink:to="lab_us-gaap_SegmentReportingCodmProfitLossMeasureHowUsedDescription" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualAxis" xlink:label="loc_srt_TitleOfIndividualAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_TitleOfIndividualAxis" xml:lang="en-US">Title and Position [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_TitleOfIndividualAxis" xlink:to="lab_srt_TitleOfIndividualAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:label="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_TitleOfIndividualWithRelationshipToEntityDomain" xml:lang="en-US">Title and Position [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_TitleOfIndividualWithRelationshipToEntityDomain" xlink:to="lab_srt_TitleOfIndividualWithRelationshipToEntityDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsAxis" xlink:label="loc_srt_ConsolidationItemsAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_ConsolidationItemsAxis" xml:lang="en-US">Consolidation Items [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_ConsolidationItemsAxis" xml:lang="en-US">Consolidation Items [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ConsolidationItemsAxis" xlink:to="lab_srt_ConsolidationItemsAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ConsolidationItemsDomain" xlink:label="loc_srt_ConsolidationItemsDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_ConsolidationItemsDomain" xml:lang="en-US">Consolidation Items [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_srt_ConsolidationItemsDomain" xml:lang="en-US">Consolidation Items [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ConsolidationItemsDomain" xlink:to="lab_srt_ConsolidationItemsDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_IntersegmentEliminationMember" xlink:label="loc_us-gaap_IntersegmentEliminationMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_IntersegmentEliminationMember" xml:lang="en-US">Intersegment Eliminations [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_IntersegmentEliminationMember" xml:lang="en-US">Intersegment Eliminations</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IntersegmentEliminationMember" xlink:to="lab_us-gaap_IntersegmentEliminationMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OperatingSegmentsMember" xlink:label="loc_us-gaap_OperatingSegmentsMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OperatingSegmentsMember" xml:lang="en-US">Operating Segments [Member]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_OperatingSegmentsMember" xml:lang="en-US">Operating Segments</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingSegmentsMember" xlink:to="lab_us-gaap_OperatingSegmentsMember" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OperatingIncomeLossAdjusted" xlink:label="loc_hmh_OperatingIncomeLossAdjusted" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OperatingIncomeLossAdjusted" xml:lang="en-US">Operating Income (Loss), Adjusted</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_OperatingIncomeLossAdjusted" xml:lang="en-US">Total segment operating income (loss)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OperatingIncomeLossAdjusted" xlink:to="lab_hmh_OperatingIncomeLossAdjusted" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_OperatingIncomeLossAdjusted" xml:lang="en-US">Operating Income (Loss), Adjusted</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_SegmentReportingOtherItemAmount" xlink:label="loc_us-gaap_SegmentReportingOtherItemAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_SegmentReportingOtherItemAmount" xml:lang="en-US">Segment Reporting, Other Segment Item, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:label="lab_us-gaap_SegmentReportingOtherItemAmount" xml:lang="en-US">Unallocated corporate costs</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SegmentReportingOtherItemAmount" xlink:to="lab_us-gaap_SegmentReportingOtherItemAmount" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_DepreciationAndAmortization" xlink:label="loc_us-gaap_DepreciationAndAmortization" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_DepreciationAndAmortization" xml:lang="en-US">Depreciation, Depletion and Amortization, Nonproduction</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DepreciationAndAmortization" xlink:to="lab_us-gaap_DepreciationAndAmortization" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_GeographicAreasRevenuesFromExternalCustomersAbstract" xlink:label="loc_us-gaap_GeographicAreasRevenuesFromExternalCustomersAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_GeographicAreasRevenuesFromExternalCustomersAbstract" xml:lang="en-US">Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue [Abstract]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_GeographicAreasRevenuesFromExternalCustomersAbstract" xlink:to="lab_us-gaap_GeographicAreasRevenuesFromExternalCustomersAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" xml:lang="en-US">Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" xlink:to="lab_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" xlink:label="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" xml:lang="en-US">Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" xlink:to="lab_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NoncurrentAssets" xlink:label="loc_us-gaap_NoncurrentAssets" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NoncurrentAssets" xml:lang="en-US">Long-Lived Asset, Excluding Financial Instrument, Customer Relationship, Mortgage Servicing Right, Deferred Policy Acquisition Cost, and Deferred Tax Asset, Amount</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoncurrentAssets" xlink:to="lab_us-gaap_NoncurrentAssets" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_US" xlink:label="loc_country_US" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_country_US" xml:lang="en-US">UNITED STATES</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_US" xlink:to="lab_country_US" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_GB" xlink:label="loc_country_GB" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_country_GB" xml:lang="en-US">UNITED KINGDOM</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_GB" xlink:to="lab_country_GB" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_SG" xlink:label="loc_country_SG" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_country_SG" xml:lang="en-US">SINGAPORE</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_SG" xlink:to="lab_country_SG" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_SA" xlink:label="loc_country_SA" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_country_SA" xml:lang="en-US">SAUDI ARABIA</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_SA" xlink:to="lab_country_SA" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_AE" xlink:label="loc_country_AE" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_country_AE" xml:lang="en-US">UNITED ARAB EMIRATES</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_AE" xlink:to="lab_country_AE" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_BR" xlink:label="loc_country_BR" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_country_BR" xml:lang="en-US">BRAZIL</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_BR" xlink:to="lab_country_BR" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_AZ" xlink:label="loc_country_AZ" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_country_AZ" xml:lang="en-US">AZERBAIJAN</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_AZ" xlink:to="lab_country_AZ" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_AU" xlink:label="loc_country_AU" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_country_AU" xml:lang="en-US">AUSTRALIA</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_AU" xlink:to="lab_country_AU" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_CA" xlink:label="loc_country_CA" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_country_CA" xml:lang="en-US">CANADA</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_CA" xlink:to="lab_country_CA" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_OtherMember" xlink:label="loc_hmh_OtherMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_OtherMember" xml:lang="en-US">Other [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_OtherMember" xlink:to="lab_hmh_OtherMember" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/country/2026/country-2026.xsd#country_NL" xlink:label="loc_country_NL" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_country_NL" xml:lang="en-US">NETHERLANDS</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_country_NL" xlink:to="lab_country_NL" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_FinancingInterestExpense" xlink:label="loc_us-gaap_FinancingInterestExpense" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_FinancingInterestExpense" xml:lang="en-US">Financing Interest Expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancingInterestExpense" xlink:to="lab_us-gaap_FinancingInterestExpense" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_OtherNoninterestExpense" xlink:label="loc_us-gaap_OtherNoninterestExpense" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_OtherNoninterestExpense" xml:lang="en-US">Other Noninterest Expense</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OtherNoninterestExpense" xlink:to="lab_us-gaap_OtherNoninterestExpense" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xml:lang="en-US">Antidilutive Security, Excluded EPS Calculation [Table]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xml:lang="en-US">Antidilutive Security, Excluded EPS Calculation [Table]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" xlink:to="lab_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xml:lang="en-US">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xml:lang="en-US">Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" xlink:to="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems" />
          <link:loc xlink:type="locator" xlink:href="hmh-20260630.xsd#hmh_SharesIssuedInCurrentPeriodExcludedFromCalculationOfBasisAndDilutedEarningsPerShareInPriorPeriod" xlink:label="loc_hmh_SharesIssuedInCurrentPeriodExcludedFromCalculationOfBasisAndDilutedEarningsPerShareInPriorPeriod" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_hmh_SharesIssuedInCurrentPeriodExcludedFromCalculationOfBasisAndDilutedEarningsPerShareInPriorPeriod" xml:lang="en-US">Shares Issued In Current Period Excluded From Calculation Of Basis And Diluted Earnings Per Share In Prior Period</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_hmh_SharesIssuedInCurrentPeriodExcludedFromCalculationOfBasisAndDilutedEarningsPerShareInPriorPeriod" xml:lang="en-US">Number of shares issued in 2026 that are excluded from calculation of basis and diluted EPS in 2025</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_hmh_SharesIssuedInCurrentPeriodExcludedFromCalculationOfBasisAndDilutedEarningsPerShareInPriorPeriod" xlink:to="lab_hmh_SharesIssuedInCurrentPeriodExcludedFromCalculationOfBasisAndDilutedEarningsPerShareInPriorPeriod" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="lab_hmh_SharesIssuedInCurrentPeriodExcludedFromCalculationOfBasisAndDilutedEarningsPerShareInPriorPeriod" xml:lang="en-US">Shares Issued In Current Period Excluded From Calculation Of Basis And Diluted Earnings Per Share In Prior Period</link:label>
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_NetIncomeLossAbstract" xlink:label="loc_us-gaap_NetIncomeLossAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_NetIncomeLossAbstract" xml:lang="en-US">Net Income (Loss) Attributable to Parent [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_NetIncomeLossAbstract" xml:lang="en-US">Numerator (in thousands)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetIncomeLossAbstract" xlink:to="lab_us-gaap_NetIncomeLossAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract" xlink:label="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract" xml:lang="en-US">Weighted Average Number of Shares Outstanding Reconciliation [Abstract]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract" xml:lang="en-US">Denominator (actual shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract" xlink:to="lab_us-gaap_WeightedAverageNumberOfSharesOutstandingDilutedDisclosureItemsAbstract" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment" xlink:label="loc_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Diluted, Adjustment</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment" xml:lang="en-US">Effect of dilutive securities (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment" xlink:to="lab_us-gaap_WeightedAverageNumberDilutedSharesOutstandingAdjustment" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xml:lang="en-US">Antidilutive Securities [Axis]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xml:lang="en-US">Antidilutive Securities [Axis]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:to="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesNameDomain" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AntidilutiveSecuritiesNameDomain" xml:lang="en-US">Antidilutive Securities, Name [Domain]</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AntidilutiveSecuritiesNameDomain" xml:lang="en-US">Antidilutive Securities, Name [Domain]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain" xlink:to="lab_us-gaap_AntidilutiveSecuritiesNameDomain" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xml:lang="en-US">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</link:label>
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xml:lang="en-US">Antidilutive securities excluded from computation of earnings per share (in shares)</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:to="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" />
          <link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd#srt_ChiefExecutiveOfficerMember" xlink:label="loc_srt_ChiefExecutiveOfficerMember" />
          <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="lab_srt_ChiefExecutiveOfficerMember" xml:lang="en-US">Chief Executive Officer [Member]</link:label>
          <link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ChiefExecutiveOfficerMember" xlink:to="lab_srt_ChiefExecutiveOfficerMember" />
        </link:labelLink>
      </link:linkbase>
    </appinfo>
  </annotation>
  <import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
  <import namespace="http://xbrl.org/2020/extensible-enumerations-2.0" schemaLocation="https://www.xbrl.org/2020/extensible-enumerations-2.0.xsd" />
  <import namespace="http://www.xbrl.org/dtr/type/2024-01-31" schemaLocation="https://www.xbrl.org/dtr/type/2024-01-31/types.xsd" />
  <import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
  <import namespace="http://www.xbrl.org/2006/ref" schemaLocation="http://www.xbrl.org/2006/ref-2006-02-27.xsd" />
  <import namespace="http://fasb.org/srt/2026" schemaLocation="https://xbrl.fasb.org/srt/2026/elts/srt-2026.xsd" />
  <import namespace="http://xbrl.sec.gov/country/2026" schemaLocation="https://xbrl.sec.gov/country/2026/country-2026.xsd" />
  <import namespace="http://xbrl.sec.gov/dei/2026" schemaLocation="https://xbrl.sec.gov/dei/2026/dei-2026.xsd" />
  <import namespace="http://xbrl.sec.gov/country/2026" schemaLocation="https://xbrl.sec.gov/country/2026/country-2026.xsd" />
  <import namespace="http://xbrl.sec.gov/currency/2026" schemaLocation="https://xbrl.sec.gov/currency/2026/currency-2026.xsd" />
  <import namespace="http://xbrl.sec.gov/exch/2026" schemaLocation="https://xbrl.sec.gov/exch/2026/exch-2026.xsd" />
  <import namespace="http://xbrl.sec.gov/stpr/2026" schemaLocation="https://xbrl.sec.gov/stpr/2026/stpr-2026.xsd" />
  <import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
  <import namespace="http://www.xbrl.org/2003/XLink" schemaLocation="http://www.xbrl.org/2003/xl-2003-12-31.xsd" />
  <import namespace="http://www.w3.org/1999/xlink" schemaLocation="http://www.xbrl.org/2003/xlink-2003-12-31.xsd" />
  <import namespace="http://fasb.org/srt-types/2026" schemaLocation="https://xbrl.fasb.org/srt/2026/elts/srt-types-2026.xsd" />
  <import namespace="http://fasb.org/us-gaap/2026" schemaLocation="https://xbrl.fasb.org/us-gaap/2026/elts/us-gaap-2026.xsd" />
  <import namespace="http://xbrl.sec.gov/naics/2026" schemaLocation="https://xbrl.sec.gov/naics/2026/naics-2026.xsd" />
  <import namespace="http://xbrl.sec.gov/sic/2026" schemaLocation="https://xbrl.sec.gov/sic/2026/sic-2026.xsd" />
  <import namespace="http://fasb.org/us-types/2026" schemaLocation="https://xbrl.fasb.org/us-gaap/2026/elts/us-types-2026.xsd" />
  <element name="SparePartsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_SparePartsMember" substitutionGroup="xbrli:item" />
  <element name="HMHHoldingBVAndSubsidiariesMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_HMHHoldingBVAndSubsidiariesMember" substitutionGroup="xbrli:item" />
  <element name="HMHHoldingIncMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_HMHHoldingIncMember" substitutionGroup="xbrli:item" />
  <element name="HistoricalMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_HistoricalMember" substitutionGroup="xbrli:item" />
  <element name="CorporateReorganizationsAdjustmentMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_CorporateReorganizationsAdjustmentMember" substitutionGroup="xbrli:item" />
  <element name="OfferingTransactionsAdjustmentsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_OfferingTransactionsAdjustmentsMember" substitutionGroup="xbrli:item" />
  <element name="RetainedEarning" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_RetainedEarning" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="AccumulatedOtherComprehensiveIncomeLoss" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_AccumulatedOtherComprehensiveIncomeLoss" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="HedgingReserveMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_HedgingReserveMember" substitutionGroup="xbrli:item" />
  <element name="PensionRemeasurementReserveMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_PensionRemeasurementReserveMember" substitutionGroup="xbrli:item" />
  <element name="CurrencyTranslationReserveMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_CurrencyTranslationReserveMember" substitutionGroup="xbrli:item" />
  <element name="AdjustmentsToAdditionalPaidInCapitalPurchaseOfShares" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_AdjustmentsToAdditionalPaidInCapitalPurchaseOfShares" substitutionGroup="xbrli:item" xbrli:balance="debit" />
  <element name="NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuanceNet" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuanceNet" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiabilityAndTaxImpactOfReorganization" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_AdjustmentsToAdditionalPaidInCapitalTaxReceivableAgreementLiabilityAndTaxImpactOfReorganization" substitutionGroup="xbrli:item" xbrli:balance="debit" />
  <element name="SaleOwnershipInterestInNonControllingInterest" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_SaleOwnershipInterestInNonControllingInterest" substitutionGroup="xbrli:item" xbrli:balance="debit" />
  <element name="OtherComprehensiveIncomePriorToReorganizationTransactions" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_OtherComprehensiveIncomePriorToReorganizationTransactions" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="NetIncomePriorToTheCorporateReorganizationTransactions" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_NetIncomePriorToTheCorporateReorganizationTransactions" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="NetIncomeLossSubsequentToTheCorporateReorganizationTransactions" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_NetIncomeLossSubsequentToTheCorporateReorganizationTransactions" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="OtherComprehensiveIncomeSubsequentToTheCorporateReorganizationTransactions" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_OtherComprehensiveIncomeSubsequentToTheCorporateReorganizationTransactions" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="PaymentsForDevelopmentCosts" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_PaymentsForDevelopmentCosts" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="PaymentOfBorrowingCosts" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_PaymentOfBorrowingCosts" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="SettlementOfLongTermDebtNetRelatedPartyAndAccountsReceivableAndRelatedPartyAccountsReceivable" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_SettlementOfLongTermDebtNetRelatedPartyAndAccountsReceivableAndRelatedPartyAccountsReceivable" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="ContingentConsiderationInConnectionWithAcquisition" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_ContingentConsiderationInConnectionWithAcquisition" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="OrganizationConsolidationAndPresentationOfFinancialStatementsTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_OrganizationConsolidationAndPresentationOfFinancialStatementsTable" substitutionGroup="xbrldt:hypercubeItem" />
  <element name="OrganizationConsolidationAndPresentationOfFinancialStatementsLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_OrganizationConsolidationAndPresentationOfFinancialStatementsLineItems" substitutionGroup="xbrli:item" />
  <element name="AccountingPoliciesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_AccountingPoliciesTable" substitutionGroup="xbrldt:hypercubeItem" />
  <element name="AccountingPoliciesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_AccountingPoliciesLineItems" substitutionGroup="xbrli:item" />
  <element name="UnauditedProFormaConsolidatedBalanceSheetAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_UnauditedProFormaConsolidatedBalanceSheetAbstract" substitutionGroup="xbrli:item" />
  <element name="UnauditedProFormaConsolidatedBalanceSheetTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_UnauditedProFormaConsolidatedBalanceSheetTable" substitutionGroup="xbrldt:hypercubeItem" />
  <element name="UnauditedProFormaConsolidatedBalanceSheetLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_UnauditedProFormaConsolidatedBalanceSheetLineItems" substitutionGroup="xbrli:item" />
  <element name="NotesToUnauditedProFormaConsolidatedBalanceSheetTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_NotesToUnauditedProFormaConsolidatedBalanceSheetTextBlock" substitutionGroup="xbrli:item" />
  <element name="UnauditedProFormaConsolidatedStatementOfIncomeAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_UnauditedProFormaConsolidatedStatementOfIncomeAbstract" substitutionGroup="xbrli:item" />
  <element name="UnauditedProFormaConsolidatedStatementOfIncomeTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_UnauditedProFormaConsolidatedStatementOfIncomeTable" substitutionGroup="xbrldt:hypercubeItem" />
  <element name="UnauditedProFormaConsolidatedStatementOfIncomeLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_UnauditedProFormaConsolidatedStatementOfIncomeLineItems" substitutionGroup="xbrli:item" />
  <element name="UnauditedProFormaConsolidatedStatementOfIncomeTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_UnauditedProFormaConsolidatedStatementOfIncomeTextBlock" substitutionGroup="xbrli:item" />
  <element name="GoodwillAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_GoodwillAbstract" substitutionGroup="xbrli:item" />
  <element name="OtherCurrentLiabilitiesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_OtherCurrentLiabilitiesTable" substitutionGroup="xbrldt:hypercubeItem" />
  <element name="OtherCurrentLiabilitiesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_OtherCurrentLiabilitiesLineItems" substitutionGroup="xbrli:item" />
  <element name="IntangibleAssetsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_IntangibleAssetsAbstract" substitutionGroup="xbrli:item" />
  <element name="AccruedExpensesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_AccruedExpensesTable" substitutionGroup="xbrldt:hypercubeItem" />
  <element name="AccruedExpensesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_AccruedExpensesLineItems" substitutionGroup="xbrli:item" />
  <element name="IncomeTaxesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_IncomeTaxesTable" substitutionGroup="xbrldt:hypercubeItem" />
  <element name="IncomeTaxesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_IncomeTaxesLineItems" substitutionGroup="xbrli:item" />
  <element name="CommitmentsContingenciesRestructuringAndGuaranteesTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_CommitmentsContingenciesRestructuringAndGuaranteesTextBlock" substitutionGroup="xbrli:item" />
  <element name="DescriptionOfBusinessPolicyTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_DescriptionOfBusinessPolicyTextBlock" substitutionGroup="xbrli:item" />
  <element name="OfferingCostsPolicyTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_OfferingCostsPolicyTextBlock" substitutionGroup="xbrli:item" />
  <element name="ShareCapitalPolicyTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_ShareCapitalPolicyTextBlock" substitutionGroup="xbrli:item" />
  <element name="AccruedLiabilitiesPolicyTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_AccruedLiabilitiesPolicyTextBlock" substitutionGroup="xbrli:item" />
  <element name="OrganizationCostsPolicyTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_OrganizationCostsPolicyTextBlock" substitutionGroup="xbrli:item" />
  <element name="ScheduleOfPropertyPlantAndEquipmentUsefulLifeTableTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTableTextBlock" substitutionGroup="xbrli:item" />
  <element name="AssetsAndLiabilitiesLesseeTableTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_AssetsAndLiabilitiesLesseeTableTextBlock" substitutionGroup="xbrli:item" />
  <element name="ScheduleOfWeightedAverageRemainingTermAndWeightedAverageDiscountRatesTableTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_ScheduleOfWeightedAverageRemainingTermAndWeightedAverageDiscountRatesTableTextBlock" substitutionGroup="xbrli:item" />
  <element name="ScheduleOfAccruedExpensesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ScheduleOfAccruedExpensesTable" substitutionGroup="xbrldt:hypercubeItem" />
  <element name="ScheduleOfShareBasedPaymentAwardPerformanceSharesValuationAssumptionsTableTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_ScheduleOfShareBasedPaymentAwardPerformanceSharesValuationAssumptionsTableTextBlock" substitutionGroup="xbrli:item" />
  <element name="ScheduleOfCurrentLifeExpectancyAfterRetirementTableTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_ScheduleOfCurrentLifeExpectancyAfterRetirementTableTextBlock" substitutionGroup="xbrli:item" />
  <element name="ScheduleOfEffectOfOnePercentagePointDefinedBenefitObligationTableTextBlock" type="dtr-types:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_ScheduleOfEffectOfOnePercentagePointDefinedBenefitObligationTableTextBlock" substitutionGroup="xbrli:item" />
  <element name="UnderwritersMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_UnderwritersMember" substitutionGroup="xbrli:item" />
  <element name="SubsidiaryVotingPowerPercentage" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_SubsidiaryVotingPowerPercentage" substitutionGroup="xbrli:item" />
  <element name="CompanyAndNonControllingInterestsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_CompanyAndNonControllingInterestsMember" substitutionGroup="xbrli:item" />
  <element name="CustomerOneMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_CustomerOneMember" substitutionGroup="xbrli:item" />
  <element name="CustomerTwoMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_CustomerTwoMember" substitutionGroup="xbrli:item" />
  <element name="BakerHughesHoldingsLLCMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_BakerHughesHoldingsLLCMember" substitutionGroup="xbrli:item" />
  <element name="AkastorASMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_AkastorASMember" substitutionGroup="xbrli:item" />
  <element name="MercuryHoldCoIncMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_MercuryHoldCoIncMember" substitutionGroup="xbrli:item" />
  <element name="BakerHughesAndAkastorMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_BakerHughesAndAkastorMember" substitutionGroup="xbrli:item" />
  <element name="IPOInvestorsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_IPOInvestorsMember" substitutionGroup="xbrli:item" />
  <element name="HMHBVMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_HMHBVMember" substitutionGroup="xbrli:item" />
  <element name="HydrilPCBLimitedMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_HydrilPCBLimitedMember" substitutionGroup="xbrli:item" />
  <element name="ShareBasedPaymentArrangementNoncashExpensePreIPO" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_ShareBasedPaymentArrangementNoncashExpensePreIPO" substitutionGroup="xbrli:item" xbrli:balance="debit" />
  <element name="UpfrontConsideration" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_UpfrontConsideration" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="DeferredConsideration" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_DeferredConsideration" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="ScheduleOfPropertyPlantAndEquipmentUsefulLifeAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeAbstract" substitutionGroup="xbrli:item" />
  <element name="ScheduleOfPropertyPlantAndEquipmentUsefulLifeTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeTable" substitutionGroup="xbrldt:hypercubeItem" />
  <element name="ScheduleOfPropertyPlantAndEquipmentUsefulLifeLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ScheduleOfPropertyPlantAndEquipmentUsefulLifeLineItems" substitutionGroup="xbrli:item" />
  <element name="CurrentPrepaidExpenseAndOtherAssets" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_CurrentPrepaidExpenseAndOtherAssets" substitutionGroup="xbrli:item" xbrli:balance="debit" />
  <element name="PercentageOfOwnershipInterestHeldByParent" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_PercentageOfOwnershipInterestHeldByParent" substitutionGroup="xbrli:item" />
  <element name="NonControllingInterest" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_NonControllingInterest" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="PercentageOfEconomicInterestHeldByPrincipalStockholder" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_PercentageOfEconomicInterestHeldByPrincipalStockholder" substitutionGroup="xbrli:item" />
  <element name="AdditionalPaidInCapitals" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_AdditionalPaidInCapitals" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="PercentageOfPaymentByPrincipalStockholders" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_PercentageOfPaymentByPrincipalStockholders" substitutionGroup="xbrli:item" />
  <element name="AmountOfTaxReceivableAgreement" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_AmountOfTaxReceivableAgreement" substitutionGroup="xbrli:item" xbrli:balance="debit" />
  <element name="AmountOfPrincipalStockholdersTaxReceivableAgreement" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_AmountOfPrincipalStockholdersTaxReceivableAgreement" substitutionGroup="xbrli:item" xbrli:balance="debit" />
  <element name="NoncurrentLiabilities" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_NoncurrentLiabilities" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="StateCorporateTaxRate" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_StateCorporateTaxRate" substitutionGroup="xbrli:item" />
  <element name="RepaymentsOfShareholderLoan" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_RepaymentsOfShareholderLoan" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="ProceedsFromShareholderLoan" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_ProceedsFromShareholderLoan" substitutionGroup="xbrli:item" xbrli:balance="debit" />
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  <element name="SubsidiaryDomain" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_SubsidiaryDomain" substitutionGroup="xbrli:item" />
  <element name="WarrantLiabilities" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_WarrantLiabilities" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="MaximumContingentConsideration" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_MaximumContingentConsideration" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="UndiscountedContingentConsideration" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_UndiscountedContingentConsideration" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="DrillformTechnicalServicesLtdMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_DrillformTechnicalServicesLtdMember" substitutionGroup="xbrli:item" />
  <element name="DeepBlueOilGasLimitedMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_DeepBlueOilGasLimitedMember" substitutionGroup="xbrli:item" />
  <element name="ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedAbstract" substitutionGroup="xbrli:item" />
  <element name="ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTable" substitutionGroup="xbrldt:hypercubeItem" />
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  <element name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesCustomerDeposits" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesCustomerDeposits" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesWarrantyLiability" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCurrentLiabilitiesWarrantyLiability" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="ScheduleOfFiniteLivedIntangibleAssetsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ScheduleOfFiniteLivedIntangibleAssetsAbstract" substitutionGroup="xbrli:item" />
  <element name="ProvisionForInventoryWriteDown" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_ProvisionForInventoryWriteDown" substitutionGroup="xbrli:item" xbrli:balance="debit" />
  <element name="GoodwillAcquisitionsAndMeasurementPeriodAdjustments" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_GoodwillAcquisitionsAndMeasurementPeriodAdjustments" substitutionGroup="xbrli:item" xbrli:balance="debit" />
  <element name="ESSSegmentMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ESSSegmentMember" substitutionGroup="xbrli:item" />
  <element name="PCSSegmentMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_PCSSegmentMember" substitutionGroup="xbrli:item" />
  <element name="HedgingPurposeAxis" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_HedgingPurposeAxis" substitutionGroup="xbrldt:dimensionItem" />
  <element name="HedgingPurposeDomain" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_HedgingPurposeDomain" substitutionGroup="xbrli:item" />
  <element name="ForecastedSalesMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ForecastedSalesMember" substitutionGroup="xbrli:item" />
  <element name="ForecastedPurchasesMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ForecastedPurchasesMember" substitutionGroup="xbrli:item" />
  <element name="ForecastedPurchasesOneMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ForecastedPurchasesOneMember" substitutionGroup="xbrli:item" />
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  <element name="LeaseTypeAxis" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_LeaseTypeAxis" substitutionGroup="xbrldt:dimensionItem" />
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  <element name="LesseeOperatingLeaseLiabilityMaturityLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_LesseeOperatingLeaseLiabilityMaturityLineItems" substitutionGroup="xbrli:item" />
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  <element name="SevenPointEightSevenFiveSeniorSecuredBondsDue2028Member" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_SevenPointEightSevenFiveSeniorSecuredBondsDue2028Member" substitutionGroup="xbrli:item" />
  <element name="NinePointEightSevenFiveSeniorSecuredBondsDue2026Member" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_NinePointEightSevenFiveSeniorSecuredBondsDue2026Member" substitutionGroup="xbrli:item" />
  <element name="ShareholderLoansMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ShareholderLoansMember" substitutionGroup="xbrli:item" />
  <element name="AdditionalBondIssuanceCapacityAmount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_AdditionalBondIssuanceCapacityAmount" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="InterestCoverageRatio" type="xbrli:pureItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_InterestCoverageRatio" substitutionGroup="xbrli:item" />
  <element name="MinimumLiquidityRequiredUnderDebtAgreementAmount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_MinimumLiquidityRequiredUnderDebtAgreementAmount" substitutionGroup="xbrli:item" xbrli:balance="debit" />
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  <element name="DeferredTaxAssetConsiderationPayableAmount" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_DeferredTaxAssetConsiderationPayableAmount" substitutionGroup="xbrli:item" xbrli:balance="credit" />
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  <element name="ProjectAndOtherManufacturingContractsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ProjectAndOtherManufacturingContractsMember" substitutionGroup="xbrli:item" />
  <element name="ProductSalesMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ProductSalesMember" substitutionGroup="xbrli:item" />
  <element name="ProductIncludingRelatedPartyMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_ProductIncludingRelatedPartyMember" substitutionGroup="xbrli:item" />
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  <element name="ContractWithCustomerAssetAdditions" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_ContractWithCustomerAssetAdditions" substitutionGroup="xbrli:item" xbrli:balance="debit" />
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  <element name="ContractWithCustomerLiabilityRevenueRecognizedIncludingOpeningBalance" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_ContractWithCustomerLiabilityRevenueRecognizedIncludingOpeningBalance" substitutionGroup="xbrli:item" xbrli:balance="credit" />
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  <element name="AccrualForEnvironmentalLossContingenciesCurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_AccrualForEnvironmentalLossContingenciesCurrent" substitutionGroup="xbrli:item" xbrli:balance="credit" />
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  <element name="ProductWarrantyReclassification" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_ProductWarrantyReclassification" substitutionGroup="xbrli:item" xbrli:balance="debit" />
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  <element name="TaxReceivableAgreementLiabilityNoncurrent" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_TaxReceivableAgreementLiabilityNoncurrent" substitutionGroup="xbrli:item" xbrli:balance="credit" />
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  <element name="CommonStockConvertibleSharesIssuable" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_CommonStockConvertibleSharesIssuable" substitutionGroup="xbrli:item" />
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  <element name="EquityAttributableToNoncontrollingInterestInterestRollForward" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_EquityAttributableToNoncontrollingInterestInterestRollForward" substitutionGroup="xbrli:item" />
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  <element name="GermanPlanMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_GermanPlanMember" substitutionGroup="xbrli:item" />
  <element name="NorwegianPlanMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_NorwegianPlanMember" substitutionGroup="xbrli:item" />
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  <element name="MalePensionersMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_MalePensionersMember" substitutionGroup="xbrli:item" />
  <element name="FemalePensionersMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_FemalePensionersMember" substitutionGroup="xbrli:item" />
  <element name="DefinedBenefitPlanCurrentLifeExpectancyAfterRetirement" type="xbrli:decimalItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_DefinedBenefitPlanCurrentLifeExpectancyAfterRetirement" substitutionGroup="xbrli:item" />
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  <element name="DeferredTaxLiabilitiesContractAssets" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_DeferredTaxLiabilitiesContractAssets" substitutionGroup="xbrli:item" xbrli:balance="credit" />
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  <element name="OtherAkastorCompaniesMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_OtherAkastorCompaniesMember" substitutionGroup="xbrli:item" />
  <element name="TanajibHoldingCompanyMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_TanajibHoldingCompanyMember" substitutionGroup="xbrli:item" />
  <element name="ProceedsFromTheLiquidation" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_ProceedsFromTheLiquidation" substitutionGroup="xbrli:item" xbrli:balance="debit" />
  <element name="AmountOfUnpaidPensionCost" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_AmountOfUnpaidPensionCost" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="AmountReceivableFromPensionPaymentsFormSubsidiary" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="hmh_AmountReceivableFromPensionPaymentsFormSubsidiary" substitutionGroup="xbrli:item" xbrli:balance="debit" />
  <element name="NumberOfReportableSegmentsNotDisclosedFlag" type="xbrli:booleanItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_NumberOfReportableSegmentsNotDisclosedFlag" substitutionGroup="xbrli:item" />
  <element name="OperatingIncomeLossAdjusted" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_OperatingIncomeLossAdjusted" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <element name="OtherMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="hmh_OtherMember" substitutionGroup="xbrli:item" />
  <element name="SharesIssuedInCurrentPeriodExcludedFromCalculationOfBasisAndDilutedEarningsPerShareInPriorPeriod" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="hmh_SharesIssuedInCurrentPeriodExcludedFromCalculationOfBasisAndDilutedEarningsPerShareInPriorPeriod" substitutionGroup="xbrli:item" />
</schema>
