How many movies have Mamiko Katakura and Takashi Watanabe collaborated on?

They have worked on 5 movies together! Their first movie together was Shimajiro and Fufu's Great Adventure: Save the Seven-Colored Flower! (2013) while their highest rated movie together was Shimajiro and the Rainbow Oasis (2017). They have not worked together since Shimajiro and the Rainbow Oasis (2017). They are most known for their animation films together.