How many movies have Ako Mayama and Kappei Yamaguchi acted in together?

They have worked on 4 movies together! Their first movie together was Chibi Maruko-chan (1990) while their highest rated movie together was Chibi Maruko-chan: My Favorite Song (1992). They have not worked together since One Piece "3D2Y": Overcome Ace's Death! Luffy's Vow to his Friends (2014). They are most known for their animation films together.