How are people obtaining coins via Warmane website using USD instead of Euros? Is there a specific method that allows you to load USD on a card and spend in a different currency? Most prepaid visas are not accepted internationally, and I'd assume buying coins from a third party such as IGGM warrants a ban.
Currency gets converted automatically during the payment. And if the card does not allow international transactions, changing the currency is not going to solve the issue.