You can create ad-hoc wireless networks in desktop mode, which should enable you to achieve that. Then, if your emulator supports netplay, with the two SDs connected to each other, you should be able to play by connecting to localhost

That’s in theory, in practice, we tried with a friend once, and his SD would just not connect to the ad-hoc network I had setup on mine

Sable always had a tendency to make the Deck heat up like crazy and burn through battery in no time, but otherwise it’s a great game to play in bed 😁