If function in the right leg is poor but you don’t want to use hand controls, so long as function in your left leg is good you could consider using your left foot to accelerate and brake as an alternative. If you have a weakness in the right leg and the right arm you may not be able to use hand controls and steer because you only effectively have use in one arm, using your left foot to operate a modified accelerator and the standard brake pedal may therefore be the only option, you could then steer with your left hand.
The most common solution is the “twin flip” pedal adaptation. An automatic car is fitted with two hinged accelerator pedals either side of the standard brake pedal, the accelerator pedals are interconnected so when one is pulled down the other flips up out of the way. This allows the disabled driver to drive with their left foot whilst able bodied drivers can drive conventionally with the right foot.
Alternatively a floor hinged accelerator adaptation can be fitted, this is more awkward to swap between left and right footed drivers as the whole assembly needs to be detached or re-installed.
Cars that are fitted with a floor hinged “organ pedal” accelerator require a separate pedal assembly to be fitted to the left of the brake pedal. The two pedals can then be switched electronically between the left and right pedal depending on which is required.
It is vital to have adequate training when using a left foot accelerator especially if you previously drove manual cars. The position of the left foot accelerator is where the clutch would be in a manual car and if you absent mindedly depress the “clutch” as you are slowing to stop you will get sudden unwanted acceleration instead of the braking that was intended.