Minimum-Jerk trajectory

Trajectory generation needs no introduction, my question is rather about whether PX4 can be given commands to satisfy the trajectory of fifth-order polynomial, if so how ? especially when the control system only takes acceleration as highest order command, and not the jerk. How can the feedforward acceleration play any role if at all ?

If it is possible for PX4 to follow such trajectory, does that mean…switching into offboard mode ? how does that work otherwise?