I don't think any MasterCard is using Wavecrest. Only AdvCash did and they went down. It was expected after the shut down of their visa program as well. Either there is a crackdown again crypto-supporting pre-paid cards or (most possibly) Wavecrest was not compliant with EU rules and she went down.
wavecrest weren't satisfying visa's rules. that's the reason they got shut down. there was also new regulation in gibraltar that passed on january first relating to crypto but i'm not sure whether that's directly related.
as there is no other eu based visa issuer i'm wondering whether wavecrest were the only ones brave enough to try it or dumb enough to ignore something. it can't be visa as a whole as cards are still possible in america.
Regulation in USA and Europe often differs so I beleive it's something that is unacceptable according to EU laws.
On the other hand really it's hard to beleive that someone would jeopardise so harsh their businesses knowing on heavy consequences.
In general, very strange situation.