Due to recent worsening of my Carpal Tunnel situation, I bought an accessibility device from Ikkegol. Unfortunately, the available instructions don't cover how to assign a pedal to the shift key and are a little unclear on how to make a pedal click. I've written How to configure an Ikkegol footswitch to remedy those issues.
I also used my Ikkegol for almost all shifting and clicking during the course of writing this article. I'll grant it's a niche article but it's the kind of thing where if you need it, you need it. I did need it and it didn't exist so I made it.