The function of the transaction code is that when remittance from other banks abroad is handled through the "Remittance to Overseas Banks" function of personal online banking, only numbers, uppercase and lowercase letters and "-"can be entered in the payee account. To remit money to EU countries, you need to directly enter the IBAN number in the "Payee Account" without entering the account number. The payee account number in overseas remittance refers to IBAN, which is a bank account number formulated by the European Banking Standards Committee (ECBS) (IBAN number is 34-bit string at most).
Generally, you can get the IBAN number from the bank (note: domestic banks do not have the IBAN number).