I did a test run of recording a zoom meeting. I had my image set to be mirrored - but when I watched the video that I recorded, my side was not mirrored as it had been in the meeting. Is this a bug in terms of the recording not being representational of the gallery view as seen during the meeting? I have a Brio 4k and apparently, I can do a lot of things with the app called camera settings but I cannot 'pre-mirror' the signal from the camera to the zoom software.
As far as I know, mirror video should only affect your view of your video, rather than everyone's view. Some users prefer to see themselves as if they were looking at themselves in the mirror, as it would be disorienting otherwise.
Hope that helps and please make sure to mark the solution as accepted if this information is what you needed.