For this use PersonalPaymentMethod.dat file.
You can see step by step video to load Personal Payment Method Details using this Link
Please find the below sample template :
METADATA|PersonalPaymentMethod|SourceSystemOwner|SourceSystemId|LegislativeDataGroupName|AssignmentNumber|PersonalPaymentMethodCode|EffectiveStartDate|PaymentAmountType|Amount|Percentage|ProcessingOrder|OrganizationPaymentMethodCode|BankName|BankBranchNumber|BankCountryCode|BankAccountNumber|BankAccountType
MERGE|PersonalPaymentMethod|XXTEST|XXTEST_PAYMETHOD2|US Legislative Data Group|XXTEST_ASSIGN2|XXTEST_PAYMETHOD2|2021/04/19|P||100|1|Direct Deposit|American Bank|000000123|US|3456|Checking