To be frank, the EU can't really do anything about it. No matter where you slice it, Russia remains a powerful energy exporter, may it be coal, gas, oil, they have loads of the stuff, and the EU have no choice but to buy from Russia, because the alternative is a rotating black out, which would be an economic suicide - and EU is heavily dependent on Russia for energy. Before you start saying about Saudi Arabia, Australia or other energy exporters. It's still an economic suicide because the shipping cost from these countries would be much more expensive compared to a dedicated pipeline, or covering the short land distance from Russia to the EU.
Just look at China for example, they banned Australian coal in 2020 because the Prime Minister gave China a negative comment about their possible involvement in the origins of COVID. And what happened? China experienced an energy crisis, were forced to give out loans to shady companies that under delivered in their production, had to do a rotating blackout, and ultimately when the crisis was so severe, they ended up eating their words and silently bought some coal from Australia in 2021, though limited. LOL, you can almost hear Australia saying "You can't live with your own failure, and where did it bring you? back to me"
So that said, the EU will just be shooting itself in the foot if it actually stopped doing business with Russia - at least for now. Unless, it found some other means of getting energy elsewhere.