How To Pay An Expense Report In A Currency Different Than Business Unit Base Currency?

Summary:

How To Pay An Expense Report In A Currency Different Than Business Unit Base Currency? 

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There is a employee temporarily secondment from Singapore BU (SG) to Malaysia BU (MY), the employee is assigned to MY BU but he has employee bank account under SG in SGD. We import his employee bank account in SGD. While he submit expense report and expense invoice is created. However, the expense invoice cannot show his SGD bank account.

Suspected the employee bank account is not marked for foreign payment used. Please advise how to update the FOREIGN_PAYMENT_USE_FLAG in UI/HDL load.