Comment by eloeffler

Just leaving some links here because I had been researching this intensively before a planned shoulder surgery:

(Definitely adding this to my list)

Frogpad: German language one handed keyboard. Unfortunately discontinued http://frogpad.com/

Mirrorboard (my favorite): Intruiging mirror solution that builds upon the assumption that it is easier to access muscle memory from the other hand when you've learned it before https://blog.xkcd.com/2007/08/14/mirrorboard-a-one-handed-ke...

Mistel Barocco fully split Keyboard: Can (and unfortunately must) be programmed without software. Right half is the main keyboard. Left side connects to it, works also in standalone mode but is not programmable then. https://mistelkeyboard.com/products/bd20945a731491407807e80d...