My gut feel is that would be a good use of electric propulsion on a boat:
- they typically don’t go far from their launch point so a low battery warning is easily handled
- they want high torque for good acceleration
- many are used only for short bursts when afloat
- they burn a lot of fuel
- they are often stored at home where charging is feasible
- they have a reputation for making lots of noise
- presumably a motor is smaller than the IC engine and associated gubbins so leaves more space for battery
- potentially can be used in places where petrol engines are banned
