gameboy, gameboy color and gameboy advance test for the below 160$ dikdoc retro cm3 open source retro game emulation handheld, houses a raspberry pi CM 3+ compute module, which is as powerful as a raspberry pi 3b+ and runs very user friendly retropie emulationstation firmware with 15000 preloaded roms.
since the aspect ratio is 3:2 GBA games looks stunning and as legitimate as it gets on the IPS panel!

Get the Handheld:

(ebay is too expensive so i didn’t add a link)