I have an old Raspberry Pi 1 (!) still going strong with Batocera Linux running NES, SNES and Mega Drive (Genesis) emulators.
I’m looking for easy multiplayer games that can be played with a 5yo. Non violent and ideally co-op, bonus points if somewhat educational.
TMNT Turtles in Time on SNES. Its a fun game and kids can button mash, and turtles are still relevant today. Puzzle games like tetris can be good for using the brain. There were a ton of puzzle games in the snes era, like bust a move (puzzle bobble), yoshi’s cookie, puyo puyo (kirby’s avalanche), and many more.
I would mostly avoid NES because it looks really dated, aside from a handful of the real classics like Super Mario Bros 1 & 3.
Those beat em ups are a great way to spend time together. As long as you can keep continuing, you barely need to pay attention and it gives you something to talk about.