This question is weirdly worded so I want to be careful answering it. This is highly device dependent, and out of these devices I only have the 8T. Will it be the same as stock camera experience? Not unless the vendor blobs and camera frameworks are ported to these OS, which they almost never are. But camera drivers still used pulled from vendor image, just with an opensource camera app.

Status of the 8T's cameras: In the 8T's case 3 of the 4 back cameras are accessible in LineageOS (only 2mp monochrome is not), and only through Gcam or Opencamera, not the stock LineageOS app. The macro camera's access was only figured out in the past few weeks by the LOS maintainer. I use a modified version of GCam to access the other lenses. I believe Oneplus actually disabled the macro lens in their vendor rom, so this is a case where LineageOS and downstream roms from it like Calyx are adding back some functionality that was lost.

AOSP Camera can't use them but GrapheneOS ships with a Camera app that's able to use all the cameras and a lightweight variant of HDR+. Google Camera can also be used on GrapheneOS simply by installing GSF and Google Camera. Network permission can optionally be revoked for both, and neither has special privileges. It's different on CalyxOS where using Google Camera requires giving a high level of privileges to Google Camera itself and Google services (microG).