'Game of Thrones' actress Bella Ramsey and 'BFG' star Ruby Barnhill will also lend their voices to the animated feature from Germany's Studio 100 Film.
John Hannah (The Mummy) and Franka Potente (The Bourne Supremacy) have joined the voice cast of the animated feature Princess Emmy.
Ruby Barnhill, one of the child stars of Steven Spielberg's The BFG, and British actress Bella Ramsey, famous for her role as Lyanna Mormont on HBO's Game of Thrones, will also voice characters in the upcoming feature from director Piet de Rycker (Laura's Star).
Germany's Studio 100 Film is producing Princess Emmy, together with Britain's Talking Horse, Belgium group Witebox and Germany's Animationsfabrik.
Studio 100 is also handling worldwide sales on the project, which is set for a June delivery.
Princess Emmy follows a young princess who risks everything to secure the magical power to talk to horses. Studio 100 has already presold the title to more than 100 countries worldwide, including to TF1 Studio in France and China's Bright Media.