catsandencryption FWIW almost all of those features require network connection to Goolag. Camera features, Photos editing features, Recorder voice transcription and maybe something else I don't know about are the few that can be used offline. Coincidentally you can use all the mentioned apps on GOS too, just let them download their thing first and their features will continue to work once you revoke Network permission. Graphene even provides hardware boost that Pixels have for these apps.
Some other PixelOS features have been backported but most of them have some caveats:
Now Playing - ported as Ambient Music Mod and uses a modified stripped down version of Android Intelligence
caveats:
- needs Shizuku
- since there is no support for wake word detection it turns on mic in intervals which drains battery a lot faster than the original Pixel feature
Double Tap - ported as Tap Tap by the same author, uses phone Sensors to detect tapping
caveats:
- not as accurate as original, sometimes falsely registers the double tap
Smartspace - ported as Smartspacer by the same author, no caveats really, some launchers may come with own version of this
Circle to Search - ported as MICTS, works on GOS phones without giving any permissions
caveats:
- needs another app to call the intent e.g. a key binder
- needs Google app to be installed and set up as assistant to work
Google Discover - Nova launcher has its own version of this, maybe other launchers too