The Pitbull

This hefty dude is designed to replace WASD for keyboard and mouse games. 

Users that have bought these have mostly been those with cerebral palsy. People have told me that it's easy to grip, and it's got some weight to it, so you don't have to worry about stability with it. 

When you plug the device in via USB-C, it registers as a USB keyboard, so it's compatible with just about anything. 

If you're using a Mac, I recommend using an adapter, one of the USB-C to USB-A adapters.

I can also make this function as a mouse for a little more cost. Instead of the traditional joystick, it would be one that has two buttons built in, kind of like a flight stick, then you could press one for left-click and the other for a right-click.