Do you have a specific legislation that is relevant to a new 2.5% fee charged on a particular method of payment transfer on eBay alone ?

All of the banking institutions have been under scrutiny of late inclusive of PayPal.
eBay continue to facilitate PayPal payments.

when you say " apparently you expect ebay to perform this function for free "

..what is the function ?

compliance ? , or "managing " a bank to bank transfer that never needed management in the first place as both sending and receiving institutions are far more equipped, and regulated, to manage the movement ?

None of my bank common bank transfers, PayPal payments, AfterPay transactions have incurred additional fees due to Royal Commission outcomes, or Aus. track

If this 2.5% fee is eBay relaying their compliance charges on to their members then why is it not over all transactions ?

Items paid with PayPal are pretty much structured the way they always have been.

I get the feeling we'll just disagree, so I'll move on from K-pop to Let it Be

All the best to you.