will it work?

If it has a one-way bearing and you flipped it around, then it would only work in reverse I think...

The proper way to use it would be to use a jackshaft like the sickbikeparts shifter kit to drive the nuvinci from the right side.

I would love to have a nuvinci connected to the motor. Too bad they're so darn expensive. For the cost of the nuvinci and shift kit, I can buy a used but working motorcycle