Same topic I think

https://my.aximmetry.com/post/455-how-to-achieve-the-effect-of-virtual-scre

I must say you are really a good man

Also, how does the SE version implement camera tracking?

Hi,
Camera tracking works the same way in SE,  just use a TrackedCam_xxxx compound instead of TrackedCam_Unreal_xxxx one.
For further info, please read:
https://aximmetry.com/wiki/index.php?title=Setting_Up_Virtual_Sets_with_Tracked_Cameras