Let say Sector Steve Top Hat needed a new propulsion system and he fitted a paddle wheel pivoted off his stern and at the axel point of the paddle wheel there were floats fitted so it always at the same height as required to drive the paddle wheel and when sailing it generated power back into Steve battery system or could be lifted out of the water so there was no other restriction than the hull speed design
and driver and generator would be a belt driven electric motor / generator
So you would mount two arms off the top hats stern and extend them out for the paddle wheel clearance and a simple winch to raise the paddle wheel out of the water when not need
It would basically be like a trailing arm suspension on a car
Id say it would have a different diameter pulley's when generating power than when driving the hull
How would it feel to steer as your an old paddle streamer skipper
The other plus would be it could be used as boarding platform as well