I'm not the right person to ask... however I strongly believe that you can sell/buy crypto currency for another crypto currency anywhere (if not in the world then at least Europe). You don't need license, permit, pay taxes - all that until you get involved with real world. No matter what when you sell crypto for fiat money or benefit from it (buying house, weed, computer, ..., whatever) you have to pay taxes from your profit.
JUST MY OPINION -︀ CAN BE WRONG