Nintendo 3DS monumental es creada con una Steam Deck y una tablet Samsung – FayerWayer
Modder creates dual screen Steam Deck in Nintendo DS tribute - Dexerto
Someone Turned Their Steam Deck into a Working DS - RetroResolve
Steam Deck DualScreen addon idea. For 3DS and NDS emu. Or multitasking. You'd plug it into the top USB-C port. There is a fan there, but perhaps it could leave a hole