Tricopter Tiltrotor VTOL

Until now PX4 supports an Y6 tiltrotor VTOL but no Tricopter Basic-VTOL-Frames.
What options are there to implement a Tricopter Tiltrotor VTOL to which I am very interested ?

Correct me if i’m wrong, but wouldnt the y6 just work on Y3?

Unfortunately no, y3-Copter needs another servo for the rear motor to compensate for the torque around the vertical axis while hoovering