This 19th century style follow focus has been gathering dust in the closet for five years. It’s got A/B hard stops and comes with a crank and a whip for smoother focus pulls, so hopefully it’s idiot-proof, which didn’t prevent me from putting it on backwards! I ordered a SmallRig lens support this afternoon, so with any luck, I can try it out in a couple of weeks. The lens is the Meike T2.1 75mm s35 EF mount.
Did you consider the wireless followfocus also from Tilta? Nano, i think.
I’m looking into it.