I've tried using foot pedals like this before but there were two issues which made it not work.

1. You need to keep the ball of your foot raised when not pressing the button, which leads to an ache super quick. And foot switches tend to be pretty tall. The actuation distance is also pretty large.

2. The fact your foot is raised messes up your sitting balance. And you need to keep your foot in the same place all the time: no spinning your chair, no leaning to the side, shifting your weight, etc.

I'd like to see a good foot input device. Maybe something attached to the foot?