Solium Infernum: https://store.steampowered.com/app/1893810/Solium_Infernum/

Brilliantly original strategy game where you play demon lords fighting for rule of hell. Amazing, complex strategy where you need to use insults, threats, challenges and diplomacy just as much as military and magical power to win. Incredible art and writing and incredibly fun and deep gameplay. Warning: you may ruin friendships over this game, you can really do devastating stuff to each other once player abilities ramp up in the later game.

It’ll teach them teamwork XD

I will put in a strong vote for Castle Crashers, one of the most fun, charismatic beat em ups of all time, imo. Would be perfect for kids that age.

Overcooked is one of the most popular co-op games of the last few years, simple concept but fun, frantic gameplay. It’s pretty cheap at base price but goes on sale pretty regularly too.

Would have to get it through Steam I believe.

Why?