OpenCamera is so far the best that works. I often use the white balance settings, exposure settings, focus, and zoom. I tried another FOSS camera (I forget the name, not on F-Droid either) that supposedly have real-time filter, but it doesn't launch on my phone.
So eventually I always use Darktable on desktop if I want to enhance my photos from my phone. Although depending on the scene lights as well, white balance settings in OpenCamera can be good enough to produce nice looking photo.