A stepper would be the easiest thing because if you know it takes 10 steps to fully open from fully closed, you could keep track of how many steps you have sent each direction in Home Assistant and be able to display the current status. 
If you want a knob on the wall that controls this, I think somewhere behind it you are still going to need a control system that translates wall switch inputs into stepping logic. Home Assistant would be able to do that easily.