Don't break your other arm too.
Just kidding, sorry for your injury and get well soon.
As for a real tip, since you mentioned software engineer specifically, I think you are using the keyboard a lot, so you obviously must've looked into voice/speech to text related stuff, but for the mouse usage, I can recommend those small form factor wireless/bluetooth keyboards with the touchpad portion in the top center, those are fairly easy to use even with the non dominant hand (or even with the fingertips of the broken side, if you can move those). I won't link here directly, but they look like small game controllers and are relatively cheap, are also called media pc keyboards or home theater, media center keyboards etc.
As for a real tip, since you mentioned software engineer specifically, I think you are using the keyboard a lot, so you obviously must've looked into voice/speech to text related stuff, but for the mouse usage, I can recommend those small form factor wireless/bluetooth keyboards with the touchpad portion in the top center, those are fairly easy to use even with the non dominant hand (or even with the fingertips of the broken side, if you can move those). I won't link here directly, but they look like small game controllers and are relatively cheap, are also called media pc keyboards or home theater, media center keyboards etc.