Yes, Serbia Banks are not the best to work with - back then Serbian Clients claimed weeks of Processing Time for SWIFT EUR Payments from UAE to Serbia.In Serbia, every bank is obligated to participate in IPS ( instant payment system in in country) and all transfers are instant.
So i think every bank will support Sepa.
Ones which do not, they will simple loose clients.
I sent payout of 15.000 EUR few days ago via Swift, and fee was 60 EUR.
same here from Wise -> Raiffeisen bank almost instant if in opening hours of Raiffeisen bank.Revolut Uk -> Raiffeisen bank, max 1 hour.