Yeah sure, I know about union-fuse, done that with success.
The only part I’m not sure about is Plex best practices in order not to get banned 
For example, I read some posts saying that when remounting an ACD mount, the modification time of files could changed thus forcing a Plex automatic update.
But if there’s no ban on ACD because of Plex scan, i may just be paranoid !
Thnaks for the answer