This is what Martin Lewis says....
The top pick cards are Revolut and WeSwap. There’s much of a muchness between them. Both give best prevailing interbank exchange rates and can be used in euros, dollars and other currencies - though Revolut works in slightly more countries. If you want your money quickly Revolut won’t charge a fee, and is best for those withdrawing smaller amounts, under £500 a month. While WeSwap is best for those withdrawing larger amounts, over £200ish at a time. Otherwise there are fees.