You can create a stereo track from two video layers on the timeline as long as they share the same metadata.
To create a stereo track from two video layers:
(a) Selected layers
The video layers are changed to stereo layers, and the track identifiers identify the left eye and right eye layers. The timeline interface is updated to reflect the components specific to a stereo track.
(a) Stereo track identifiers
If there was a soft effect on one of the two video layers, a red bar appears between the layers to indicate that the layers are not in stereo sync.