As a slightly related precedent, some early trucks used an engine->generator->wires->electric motor system as an electric transmission as this worked better tha

As a slightly related precedent, some early trucks used an engine->generator->wires->electric motor system as an electric transmission as this worked better than the early gearboxes. On a bicycle, the wiring would certainly be easy and considerably lighter than shafts, chains or hydraulics. You would take a hit on efficiency as pedaling force would have to be converted to electricity and then back to motion, but generators and motors are pretty good these days. Weight could be an issue, but again the developments in hub motors have seen the weight come down a lot to the point that your idea seems viable.