Coverview only for specific folders

[DRONE7]

Weird arrangement, with cover doubled even from the same folder e.g. "Various Artist - Beautiful album", it shows me every single track from the album just because are played by different artists.

You don't have the tag view option set....?
 M>Preferences>Library(Advanced)>Tag View Artist

select the green info icon and read the options then select the one you need..

Select how to populate the Artist list in Tag view.
Artist: List all Artists, Performers and Conductors. Compilation albums listed for a selected artist will show only the tracks belonging to the artist. Clicking the Album will toggle between showing all the album's tracks and just those for the selected artist.
Album Artist: List all Album Artists. Compilation albums are listed under the Album Artist named "Various Artists" or any other string that was used to identify compilation albums.
Album Artist +: Same as Album Artists except compilation albums listed for a selected Album Artist will show only the tracks belonging to the Album Artist. Clicking the Album will toggle between showing all the album's tracks and just those for the selected Album Artist.

Failing that then you have a tagging problem with your files where the various artists tag is not set correctly.