Greece

Serbia, but it’s very marginal. Maybe Greece if you’re really optimistic. Of course Russia (+Belarus and the pro-Russian parts of Ukraine) if you count them as European. Everywhere else is pretty much devoid of revolutionary consciousness, especially Western Europe.

Maybe biased here but I have some hope for us in Belgium

Greece, maybe? Depends on what you mean by revolutionary potential. NATO is a stop to anything decent but i’m not european lol