Many tracks in my collection contains two or more artist names, always separated by commas, in %ARTIST% field, as following: Neil Diamond, Carol King.
Is there a way to convert %ARTIST% into Neil Diamond (i.e. first artist name), putting Carol King (i.e. second or more following artist names) into %ALBUMARTIST% field?
Are you absolutely sure that you don't have ARTIST names with a comma INSIDE the name, like many group names (i.e. "Emerson, Lake & Palmer" or "Crosby, Stills, Nash & Young)?
"caratteri jolly" translates into "place holder character" with google translate ...
The action I suggested should be something like "import tag field" or "import data".
Just as a side note:
You can always switch the language in Mp3tag in File -> Options -> Language.
This way you can add such an action with the suggested english names and then switch back to your (Italian) GUI language.