there was a post that big boy started some time ago but i cant find it about if there is something wireless to connect to an inboard engine so that when you are a certain distance from the engine it cuts off.
caruana marine has a man overboard device that can be used for this purpose and all you have is like a wrist watch in your hand and an piece of electronic to the starter of the motor.
it can also be used for man overboard satey device. the crew member all wear this wrist watch and the eltronic device is attached to a buzzer and if someone falls overboard the buzzer goes on.
you have to be a distance of 10 meters from eletronic devise to work. it costs about 450 euros
Expensive busu I think the other one is a lot cheaper