Linking 2 rudders to apm board

Good day to you all,

i have some questions but i cant find the right forum area for it. but it involves a boat and apm/flight controller. so this is the most right location i could find.

i have a 90 cm long by 25 cm wide and 35 cm high rc boat… a towing tug with working towing winch.
it haves 2 engines and 2 rudders.

the 2 rudders are now controlled by a single servo with a crossbar between them.
but i like to change that to 2 servo’s, can those servos controlled independent of each other
and by switching a switch they are linked together is that possible?

it could be done with a script on a pixhawk but I dont think there is any way of doing it on an APM.