How many movies have Koichi Usami and Tetsuya Matsukawa collaborated on?

They have worked on 3 movies together! Their first movie together was Mobile Suit Gundam 00: A Wakening of the Trailblazer (2010) while their highest rated movie together was Donten: Laughing Under the Clouds - Gaiden: Chapter 3 - Conspiracy of the Military (2018). They have not worked together since Donten: Laughing Under the Clouds - Gaiden: Chapter 3 - Conspiracy of the Military (2018). They are most known for their animation films together.