The Analogue.
This one looks like an update to the GameBoy Pocket, but it can run any GaneBoy cart and with adapters also NeoGeo Pocket, Lynx and Game Gear carts.
It can also dock and play on your TV like the Switch (with a Bluetooth controller).
Also it has a built in music synthesizer.
Is it worth $200? Probably not. But it's pretty cool all the same.
Does it have a crank?
If not, it should have a crank.
Is there actually a market for this? I'd imagine the number of people who want to play ancient handheld games, and have a collection of them to use - but somehow aren't interested in playing them on the original systems - is vanishingly small.
(Ah, it's GBA compatible at least, which makes it a slightly more interesting prospect. But still).
Metal Gear Ghost Babel machine, blessed.