Mixed corexy and hybrid-corexy kinematic for single toolhead

My random ideal when playing with Hybrid-corexy based idex. What if we only use 1 toolhead instead 2. The inner belt path(AB) is traditional corexy, and the outer belt path(Y1,Y2) are driven by 2 motors in cartesian mode.
This kind of setup will help alot with large size machines since the heavy gantry is taken care by 2y motors with short belt path. We also have double the torque for X axis.

I’m working on the code to make it work, but still not sure about the bellow points

  • Should it be a new kinematic or just a new mode for the Hybrid-corexy or corexy kinematic? I called it extended_corexy for now.
  • Endstop logic are done. But by default I have to define endstop for both B and Y rails. Since they are control the same Y axis, we only use one rail to home, so only one of them need endstop.

Bellow is my current modify based on corexy kinematic code. Seem to work well on my machine with 150 hours+ of printing.

Thank in advance!
Sorry for my bad English!