At least the Robin had the advantage of having a true differential. Pedal trikes are almost always 1-leggers - only 1 side is the drive wheel, usually RHS, which ofc means that when the drive wheel is the inside wheel on a turn, it has a much higher chance to slip. This also induces "torque steer" if you have a significant amount of motor assist under hard acceleration, on deceleration if you have no freewheel between engine and drive.
There are trike differentials and other small differentials that can be adapted. I once owned a huge rickshaw trike with a rear bench seat that had a beefy trike differential on it. Don't know how much power that little diff can handle or how effective it is. Front-wheel drive is perhaps the better way to go, IMHO.