Not quite what you're asking for, but may do the trick?
[Media Type]=[Audio] ~nodup=[Lyrics],[Artist],[Name] ~dup=[Artist],[Name] ~sort=[Name]
Will find all duplicates with different lyrics.
Or how about
Duplicates: Media Type is Audio; Only Duplicates of Artist,Name
No lyrics: Playlists is any Duplicates; Lyrics is <empty>; No Duplicates of Artist,Name
Has lyrics: Playlists is any Duplicates; Lyrics is not <empty>; No Duplicates of Artist,Name
One with, one without: Playlists is any No Lyrics, Has Lyrics; Only Duplicates of Artist,Name; Sort by Name
Should give you all duplicates where you've got at least one with lyrics and at least one without, but only a maximum of one of each.