In Europe you have SEPA. That insures that you can send EUR between all European banks instantly for free.
When I lived in Canada I really took e-transfer for granted and was surprised to learn it's not a thing in other places.
But even old school SEPA transfers shouldn't take more than a few hours nowadays, outside weekends and holidays.
I believe https://empsa.org members should eventually be interoperable with UPI, among others.
YMMV. My main bank charges 0.5% up to 20€ or something. My second bank does not.