How many movies have Akatsuki Yamatoya and Takeshi Seyama collaborated on?

They have worked on 2 movies together! Their first movie together was Gintama: The Movie (2010) while their highest rated movie together was Gintama: The Movie: The Final Chapter: Be Forever Yorozuya (2013). They have not worked together since Gintama: The Movie: The Final Chapter: Be Forever Yorozuya (2013).