2nd weapon keybinds

Wouldn’t it be amazing to have seperate keybinds for 2nd weapons?
I play a LOT of Mercy and find it much more comfortable to have my mouse buttons switched, so I can damage boost with my left mouse button and heal with my right mouse button.
However, when I am forced to pull out my pistol my brain messes with me because then I confuse left and right mouse buttons.
This may be a quality of life thing but it would be amazing to have the possibility of seperate keybinds for the two weapons .