wobbly life! i fuckiing love wobbly life it is like GTA but more physics based and family friendly. It has that perfect co-op recipe of providing focus tasks and challenges you can accomplish together but also giving ample room and opportunity for spontaneous and chaotic fun
https://store.steampowered.com/app/1211020/Wobbly_Life/
lego games are great too!
For more chill gameplay I REALLY like Farm Together, I haven't tried the second one yet.
I can recommend a lot of local-splitscreen games too.
Motortown for driving trucks but it has no splitscreen
Stunt Rally 3 has splitscreen and actually the driving feels really good in my opinion, it is free and open source!