1. show the "contra" bank account details for every transfer in and out of an account (to show who oaid or who received the funds)
2. provide bank statements in a (standardised) machine readable format
3. provide the statements within a week of request.
Such bank statements would make following the trail a lot easier.
None of the enormous, listed, multi-national banks where I live can do all three. Most can barely do 3.
They are so bad, we have had to conclude that money-laundering is actually a tacit service they offer.