How many movies have Akihiro Hirasawa and Shinobu Nishiyama collaborated on?

They have worked on 2 movies together! Their first movie together was Zone of the Enders: Idolo (2001) while their highest rated movie together was Magical Girl Lyrical Nanoha: Detonation (2018). They have not worked together since Magical Girl Lyrical Nanoha: Detonation (2018).