I have A Coolpad Y83-100 running A VibeUI Custom Rom based on MM. I have flashed Magisk V19 on it and the installation was successful , but on booting Magisk Manager shows that Magisk is Installed but Core Only Module is Enabled.I have tried disabling it , but it is re enabled after a reboot .Hence , I can't use any modules.
I can still use root and apps like Titanium Backup and Greenify works but I cant use Xposed (I have even tried Non-systemless version) or any other modules .
One thing to note that when my Phone was on the stock ROM , Magisk worked just fine.
OS:Android 6 SDK 23
CPU Variant: aarch64
ROM: VibeUI MM
Magisk Log: https://pastebin.com/z6B6rkVg