Actually the front pitch would not be that hard to accomplish. It's just a simple U-Joint connection. I have it pictured in my mind, I just can't explain it.
As for how to make it work, remember the Chinook does not have a rudder. It works in the same manner as a coax. But in this case the blades are separated. Needless to say, I would NEED the DX18 to do all of the mixing that this heli would require. aileron would tilt both rotors left and right. Elevator would add collective to the front with back, and to the back for forward. Rudder is where it gets fun. Left rudder would give left aileron to the front rotor and right aileron to the rear rotor. And collective would be up and down to both.
As you can see, there will be a total of at least 6 servos on this bird just to control the flight. Not to mention everything else that you would need. It can be done, there would just be a lot of planning to make it happen. It does have my brain in overdrive though lol.