I’ve sent money from Taiwan to Thailand using Skrill with my Chunghwa Post debit card before. But I don’t remember anymore if Skrill’s rate was 0.5% or 1.5% lower than the middle rate. What I know is that Chunghwa Post charged me on their side another 1.5% on the middle rate as Skrill only accepts payments in EUR or USD. TransferWise would be much more expensive than Skrill as just after entering the card number of your Taiwanese card the fees increase dramatically. Skrill on the other hand charges the same amount of fees no matter where your card has been issued. Using a non-Taiwanese card from a major country would still be better due to much more options to save money on transfer fees. Another option would be OFX but you would still have to wire money in USD out of Taiwan so it’s not exactly clear to me how this could be cheaper than wiring USD directly to Eastern Europe unless OFX charges lower incoming fees when you choose to share the fees of your transfer.