water10fall
i myself still noob when it comes to unity...
but i manage to config passthrough and use it on pico 4 and make like an noobish AR app that way...
it is easy and only need to add a script that activates passthrough and after you just follow tutorials how to add controllers and how to move and scale objects inside app...
on quest 2 it's more easy because there already good tutorials how to do passthrough and there already good sample with controller and objects that you can move around and scale like this one tutorial https://www.youtube.com/watch?v=SJANudr3Wu0&ab_channel=DilmerValecillos
just replace these object with a porn clip but first cut out background with tools of your choice...
just google how to add clip or picture in unity with transparent background or greenscreen...there many tutorials on that and even for how to do it for AR...
its not that hard to do and easy to figure out...^^
here two quick ways example tutorial of many:
https://www.youtube.com/watch?v=FJ5igH8sGVE&ab_channel=MikeMurphyCo
https://www.youtube.com/watch?v=ve_NQgrlfto&ab_channel=Mtir%27sCode
result should look like this:
https://www.youtube.com/watch?v=3bMbecZWLAM&ab_channel=CVLabResearch
then create app and move to your headset and enjoy play around with that clip...scale, move in position you wish in your room...
simple that.
enjoy full 6dof and girls in your room ^^
i would recommend to search for porn clips where you see full complete body of the girls or guys and where the camera don't moves much in that porn clip. with such clips and scenes it works the best.
that just one way how to do it by yourself and if doing it right...the result going be awesome and almost same immersed looking like the 180vr passthrough clips.