Bank Statement Processing

Hello,

I would like to know, how works the "Account pairing" in the Bank Statement Details.

1) Usually we open some the period from Bank Statement Summary.
2) in the Details for each the record we set Internal Operation and this arranges the automated pairing with Business Partner and Fee account.

Is somehow possible to adapt this auto-pairing with Business Partner and Fee Account?
Why? Because when the BP has set some currency(Euro) and the payment was paid from another account(CZK), so I am not able to set manually Fee account with another currency.

Thank You for any hint