The Escapists 2
Minecraft
Deep Rock Galactic

Also if you really liked Baldur's Gate 3 and really want to play something similar again try Divinity Original Sin 2, which is from the same people that made Baldur's Gate 3.

• A Way Out

• Any Lego game

• Unravel 2

• Playing a single player narrative game can be fun, where you both decide on the choices you make together. Games like Life is Strange

Dan Paladin trilogy is amazing:

Alien Hominid

Castle Crashers

Battleblock Theatre

Also some of the earlier Halo games have pretty sweet co-op campaigns too

Recently picked up Ship of Fools and think it'd be a vibe you'd like based on that list.

Trine 1-5

Overcooked! 1-2

A Way Out

Keep Talking and Nobody Explodes

Moving Out 2

pikmin though, pikmin is amazing

Luigi’s Mansion 3

Also try The Binding of Isaac: Repentance. It’s a roguelike, and honestly one of my favourite games ever. (Note: you have to get the repentance DLC as the base game does not include multiplayer (from what I remember anyway))

• Octodad: Dadliest Catch

• A hat in time

Crash Bandicoot

my girlfriend really likes borderlands 2

If you like shooters at all, try helldivers 1! Helldivers 2 just came out but the difference is that while helldivers 2 is a third person shooter, helldivers 1 is Birds Eye view, so not only does it have couch coop but it’s also far more welcoming to beginners.

Vampire Survivors has a co-op mode!

My partner and I played it and she got instantly hooked. She ended up 100%ing the solo "campaign" pretty much immediately afterwards.