Can Library be switched from sort by 'Album Artist' to sort by 'Artist' only?

[rongon]

I find that MP3TAG is actually pretty good at correcting situations where the wrong type of tag has been used.  It won't tell you your FLAC has ID3, but if you open such a file, then cut all the tags (ctrl+x) and then paste them back (ctrl+p) it will put it all back correctly.  ID3 tags become properly formatted for FLAC.

Finally, I see the way forward. 

It does look like I'll be retagging a lot of files, but Mp3tag does seem to work fine for this. 

For pop, rock, folk, blues, Latin, and most jazz titles I'll be able to simply transfer the contents of the Artist tag to Album Artist, and that should fix the indexing in Moode 8.1.2. 

Mp3tag display a Tag column, which lists what tag types are written into the file. 
I see that there are three tags written into all my files: ID3v1, ID3v2, and FLAC. 

To fix them: 

1. Select the FLAC tracks to repair.
   
2. Press Ctrl+x to cut the tags from the FLAC files and copy those tags to the clipboard. 
   
3. Leave the tracks selected. Press Ctrl+v (*not* Ctrl+p -- that creates a new playlist) to re-insert the tags into the FLAC files. 
   
4. Now you'll see only FLAC in the Mp3tag > Tags column. 
   

Thank you all for sharing your knowledge, being patient and helping me get to a solution to this problem. 
I hope the information in this thread makes this all very clear for the next person who stumbles into this tagging issue. 

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