Final Cut Pro Tracking

Are you trying a trick like explained in this youtube video?

https://www.youtube.com/watch?v=JstYyYT4OzM

In this video, the author uses negative scaling on both X and Y.

I would try, for example, setting X to -100 and Y to a small negative number close to 0.

I did not test, just speculating, but I hope it works.

I set the tracked clip y-axis to -1%, so on the visible clip you have to set the y to -10,000% to correct the scale.

I don't know exactly what settings you are actually using. Could you please share screenshots and sample videos? *Please take a photo with shift+⌘3

- Screenshot -

1. Project selection →Inspector:Change:Project properties

2. Select the mirrored clip on the timeline (original clip to be tracked) →Video inspector *control+⌘4

3. Clip selection (clip for export) with tracking data applied →Video inspector *control+⌘4

- Sample video -

4. Upload the original 16:9 file Post the link you obtained (Shared with everyone via email notification)

[Edited by Moderator]