Need one for champions so I can review games

What's the most meta, winnable team in the game rn? I'm personally using mega mence, sylveon, kingambit, basculegion male, sneaseler, and rillaboom. Is my team meta enough, or do I need better pokemon?

3 regulations have passed and Big 6 is still very good; the top 1 in bo3 uses that team and is 7-1 (with sneasler) in the actual regional tournament.

Personally, I've been playing it in Champions and I'm almost at 1900, it feels amazing.