Using "connect to folder", you can sync to external folder in whatever name format you wanted. You can use plugin like Action Chain to automatically sync the connected folder after import.
If you want to change how calibre itself store your library, you can't. It's calibre internal library. It's not to be manipulated by user.
See here for more info:
https://www.mobileread.com/forums/sh...d.php?t=119175