Best Handheld non-switch games

I've picked up the ROG and set it up with Steam, XBox store, GoG and Epic, but I'm still looking for good games that work with a controller. Hopefully as time progresses more titles will work with both controllers or Keyboard/Mouse setups, but for now what could my go to be? **Have**: Tunic, the Witcher series ( poor controller support) Undertale Especially looking for couch co-op games!