As the title suggests. While keyboards work if you plug them in there is no way of setting up stuff (layout changes etc).
Also mouse. Might be useful for those porting SFOS to tablets. (see how iPads, Surfaces are used etc)
So a section in the settings would be more than nice to have.
Ill leave this here for you https://twitter.com/adampigg/status/1319548637865705472
Saw that the other day. Awesome work. Hopefully its going to be merged in the normal SFOS release. 
BTW more HW keyboard layouts need to be available in the settings. At the moment the ones available in the settings do not match the ones that can be enabled for the Virtual keyboard.