I am in the process of building my own design of (draganflyer)
its a 4 motor/rotor flying saucer simplest way to describe it is like an X with a rotor on each end

I want to be able to control lift that is all for motors equal in speed using the throttle lever on a 4 cha transmitter
then forward motion by increasing the rear motor and decreasing the front at the same time
I want to control roll by increasing the left motor and decreasing the right equally as to keep altitude
and control yaw by slowing down 2 opposing rotors . I know this looks complicated but I am sure there is a simple solution
This can be done by custom electronics but I want to build a prototype first just by plugging bit together.
If this cant be dont is there a transmitter that cant mix up to 4 channels together for each function on a 4 channel transmitter. Sorry if the explaination is a bit vague, not my strong point. Thank you in advance. Mark