Yes this is all that needs to happen. The EU should mandate that sellers can pass transaction costs on to consumers if they want (but no more than transaction costs, looking at you airlines).
> EU should mandate that sellers can pass transaction costs on to consumers
EU actually mandates the opposite. It is illegal to pass the transaction costs to the consumer. The price you see on an item has the be the final price you end up paying.
In many online shops in EU you can see "Administrative fee" if your order is too small for example. So while companies are not allowed to do "Credit card fee" they still do it indirectly in one way or another, those that don't impose extra fee usually have higher delivery fee.
Brazil has a similar rule, but the price you see on an item is the largest one you may end up paying. So, the seller can still reduce it if you choose a cheaper payment means, and many of them do that.
I love them for it. When I don’t live in Europe it’s infuriating to see the price levitate after every checkout step. Thankfully it’s still not as bad as it used to be like 10-15 years ago.
One influence in the setting of this rule was that payment card processors had been throwing their weight around requiring that merchants not pass on cost, which was fairly clearly an abuse of their position of power. (For most in-person business, which was largely what was being dealt with at the time, cash is essentially costless, and so for some small businesses being forced to swallow payment card fees was genuinely an unreasonable burden.)
EU actually mandates the opposite. It is illegal to pass the transaction costs to the consumer. The price you see on an item has the be the final price you end up paying.