WoollyMammoth
Rattata
I thought dual screen retro handhelds would already be a thing but looks like it's just going to be the Ayaneo Flip with a 7840u. Probably going to be another $1000+ PC handheld. Besides that, the foldable Android phones look pretty good with a telescopic controller. Old Surface Duo or Galaxy Fold seem around the same price as a used new 3DS XL though. Don't know how durable the screen hinges are