I've searching any fully working GCam on forums, for my S9+ Snapdragon and I found!
It's a work from a Brazilian YT and I don't know if he just renamed/created/modded/copied another apk (he dosen't say) but I'll upload as I found.
His name is Walker and his channel is bellow, so the credits are his, I'm just bringing to us.
I've tested and it is by far better than Samsung's one.
Test yourself and give the feedback.
And Dont forget to hit the THANKS button
-Download both files (.xml and Gcam) on attachment
-Create a Folder on your phone with the name GCAM
-INSIDE the Gcam folder, create another folder named Configs and put the .XML file inside
-Install the apk as a normal file
-Open GCAM and Click on a invisible button between and give a OK to load optimal cfg (picture on the attachment)
His Channel - Thanks Walker!