With the Orchestre de Paris, under the direction of Semyon Bychkov, she performed Beethoven's Triple Concerto with cellist Natalia Gutman and Salvatore Accardo.

She played with violinist Vladimir Spivakov in Paris, St. Petersburg, Montreal, at the Colmar Festival and the Rencontres Musicales d'Evian.

She has played two pianos with Boris Berezovsky, Frank Braley, Brigitte Engerer, Cyprien Katsaris and Louis Lortie.

[1] In April 2024, Mercier appeared in a video that went viral, published by the French-Malian singer Aya Nakamura, alongside Brigitte Macron.

With the violinist Vladimir Spivakov, she recorded a disc dedicated to Ernest Chausson, under the Capriccio label.