How many movies have Koji Eto and Masaru Yanaka collaborated on?

They have worked on 5 movies together! Their first movie together was The Garden of Sinners: A Study in Murder (Part 2) (2009) while their highest rated movie together was Demon Slayer -Kimetsu no Yaiba- The Movie: Mugen Train (2020). They have not worked together since Demon Slayer -Kimetsu no Yaiba- The Movie: Mugen Train (2020). They are most known for their fantasy films together.