How many movies have Mamoru Hosoda and Youichi Oonishi collaborated on?

They have worked on 4 movies together! Their first movie together was Dragon Ball Z: Broly – The Legendary Super Saiyan (1993) while their highest rated movie together was Sailor Moon SuperS: The Movie: Black Dream Hole (1995). They have not worked together since Dragon Ball: The Path to Power (1996). They are most known for their animation films together.