Well, after tried some GCams, this is the best i've found: https://mega.nz/file/CIoDzADJ#yd19WB023DOJZo4yIRnqf6wBIlpUjsO5k44egs7E8us
It's a Mi 9 SE GCam 7.3, but it worked fine. For this camera you have to flash "buffer fix" (Magisk version is fine). The only problem i've found is that "HDR+" doesn't work well in low light, so in those situations you have to activate "HDR+ Enhaced" or Nigth Vision, because with HDR+ you get an image very very agresivelly-processed. Maybe a XLM could fix that but i haven't found it.
In case you have bootloader-locked device and can't flash buffer fix, this is best GCam: https://forum.xda-developers.com/showpost.php?p=82383905&postcount=267
That one is a Gcam 7.0 with buffer fix integrated. There's still not stable GCam 7.3 for locked devices i think.
I have locked bootloader and tried the 7.0 version.
But when I take a picture, the colors are desaturated. They become fine when I take a picture with Night mode. Should I just adjust the saturation in settings? If yes, to what amount, if you know?
And does the Astrography mode work? Or do I have to enable it in developer settings (by ticking some options)? Because it doesn't work for me. I enable it in developer options and the camera is completely still but it takes regular night mode anyway.