In Europe, most “euroskeptic” parties are also fascist parties. They have taken up the mantle of being against the EU from leftist parties. I can remember Jeremy Corbyn in the UK being skeptic and even outright against the EU. The fascists have done the same with the anti-war sentiment and it is the far-right parties who are against arming NATO and direct confrontation with Russia.
Socialists, communists have plenty to hate the EU for. A big reason is that EU law actually forbids EU states from nationalising industries and resources. For the EU, privatisation is the only way forward.
The EU is a neoliberal, neocolonial institution and is the “natural” enemy of every socialist.
In the Netherlands they are seperated
Do they write “blank votes”? That’s cool, I guess. Where I am the invalid votes go towards the winning party/candidate.