Turboprop
This could also replace the gearbox needed for a turboprop. Turbine/generator runs to produce the average power requirements at whatever speed is most efficient. A variable frequency drive takes this power, together with battery power and spins this motor at the prop's design speed. No gears needed.
Designers are also not constrained by the mechanical layouts of shaft/gearbox driven propellers. The turbine/generator(s) could be located in the wing box area with these motors out in the nacelles on the wings. There would be some aerodynamic improvements as well.
For a single turbine/generator failure, the remaining sources could still drive all the propellers (at reduced power) resulting in no yaw (and resulting correction).