I have a surf mouse which is kind of fun on my standup desk. I never really got the hang of it, but it is too cool to get rid of. https://www.surfmouse.io/ maybe it is for you.
I find that it forces standing perfectly straight and still, while I like to wobble when standing so I never use it long.
I never tried sitting with it, the FAQ says you can. YMMV.
Learning doesn't take long, just plug it in, stand on it an watch your mouse move.