Vaëz also collaborated on opera libretti with the writers Eugène Scribe and Victorien Sardou.
[4] Together they co-authored 30 stage works that mainly consisted of opera libretti and a type of play known as comédies-vaudevilles.
[2] Operas which Vaëz and Royer co-translated included Donizetti's Lucia di Lammermoor (1839);[4] Gioachino Rossini: Otello (1844);[2] and Verdi's I Lombardi (1847).
[2] Alone, Vaëz wrote the French language libretto for Donizetti's Rita, ou Le mari battu.
He also co-wrote the libretto for François-Auguste Gevaert's Le capitaine Henriot (1864) with Victorien Sardou.