If you want to see your 3D Blu-Ray videos in VR then this article on Reddit is a big help. I’ve converted quite a few 3D-BR Vid’s to use on my PiMax headset and it’s awesome.
You’ll need a fast computer (if you’re impatient like me), a good 3D capable Blu-Ray player/writer (I use a LG BP50NB40 portable, slim), a lot of spare storage space (preferably NVME - for speed), a 3D player capable of playing “SBS - Side by Side” video files, and plenty of a “soothing” beverage - coz it’s going to take a while…