I just found another couple wandering tags/duplicates:

In Il barbiere di Siviglia | The Barber of Seville - Rossini/Sterbini, two characters are duplicated.

Conte di Almaviva (Barber of Seville - Rossini)
Conte di Almaviva | Count Almaviva (Figaro Trilogy)

Figaro (Barber of Seville - Rossini)
Figaro (Figaro Trilogy)

I suspect it's because the "Figaro Trilogy" versions have wandered from Le nozze di Figaro | The Marriage of Figaro - Mozart/Da Ponte. (These two characters appear in both operas, so it makes sense for them to be there under both fandoms.)

Thanks for all your tagset work!