Yes it is possible, just use a normal mountain bike disc hub, just use twosprockets, so you may as well use more frankly, Sturmey archer three speed disc could be cool but not too light
Using a replacement rear frame means no fittings for the stock The radio, so yes you need a new shifter and the derailleur as used on a normal bicycle.
Yes it is possible, just use a normal mountain bike disc hub, just use twosprockets, so you may as well use more frankly, Sturmey archer three speed disc could be cool but not too light