So this is something I've noticed on our main vehicle, an S1000, and was just testing on the Bebop2. Whenever I slowly decelerate in posctl to center stick there is an oscillation as the vehicle is almost level. This is not present if I just let the right stick return to center by itself. My hunch was that it was related to being in and out of the RC deadzone for a brief moment and I think that may be close to the problem.
You can see it between 17:15 and 17:16 on the roll axis. There is a slight spike on the manual control input on roll which then causes the oscillation observable in roll angular rate.
The oscillation is small on the bebop, but looks large on the s1000 just due to the size difference. I used a Frsky Taranis 9D through QGC for the Bebop and a Futaba T8J with the s1000.
Is there some recommended expo settings that could alleviate this? Or some additional filtering that can be done on manual control input?