Thanks. I get it now, you are toggling TrackEntry reverse multiple times. Yes, I think this is how it is expected to work. When reversed the track time is flipped over, instead of 0 to animation duration it's animation duration to 0. Eg if you are at 25% of the animation duration, when reversed you'll be at 75%. That is very likely a different pose, so the skeleton jumps to the new pose.
The reverse setting is not typically changed during playback. To have more control you could use the timeline API. That allows you to control the animation time yourself, you can adjust it forward or backward as needed.
