Are both the Louise and the La clemenza di Tito operas?
yes
Title: La clemenza di Tito
Passage: La clemenza di Tito (English: "The Clemency of Titus"), K. 621, is an "opera seria" in two acts composed by Wolfgang Amadeus Mozart to an Italian libretto by Caterino Mazzolà, after Metastasio.  It was started after the bulk of "Die Zauberflöte " ("The Magic Flute"), the last opera that Mozart worked on, was already written.  The work premiered on 6 September 1791 at the Estates Theatre in Prague.
Title: Zelmira
Passage: Zelmira (] ) is an opera in two acts by Gioachino Rossini to a libretto by Andrea Leone Tottola.  Based on the French play, "Zelmire" by de Belloy, it was the last of the composer's Neapolitan operas.  Stendhal called its music Teutonic, comparing it with "La clemenza di Tito" but remarking: "...while Mozart would probably, had he lived, have grown completely Italian, Rossini may well, by the end of his career, have become more German than Beethoven himself!"
Title: Louise (opera)
Passage: Louise is an opera ("roman musical" ) in four acts by Gustave Charpentier to an original French libretto by the composer, with some contributions by Saint-Pol-Roux, a symbolist poet and inspiration of the surrealists.
Louise (opera) La clemenza di Tito