Directed by Eric Warin and Tahir Rana from a screenplay by Erik Rutherford and David Bezmozgis, the film will have its premiere at the Toronto International Film Festival this year.
According to Variety, the voice cast also includes Jim Broadbent, Sam Claflin, Henry Czerny, Eddie Marsan, Brenda Blethyn and Sophie Okonedo.
The movie's French version will feature the voices of actors Marion Cotillard and Romain Duris.
The animated drama is inspired by the autobiographical painting series ''Life? Or Theatre?'' by Charlotte Salomon.
It follows Charlotte Salomon, a young woman who grows up during World War II and comes out on the other side with her artistry to create a masterpiece.
Julia Rosenberg of January Films has produced the movie along with Jerome Dopffer, Eric Goossens and Anton Roebbens.
Knightley and Cotillard serve as executive producers alongside Morgan Emmery, Jean-Charles Levy, Cedric Iland, Bastien Sirodot, Robert Lantos, Jim Sternberg, Joe Iacono, Mark Musselman, Nancy Grant, and Xavier Dolan.