How many movies have Naoko Yamada and Saori Sone collaborated on?

They have worked on 2 movies together! Their first movie together was Sword Art Online: The Movie – Ordinal Scale (2017) while their highest rated movie together was Maquia: When the Promised Flower Blooms (2018). They have not worked together since Maquia: When the Promised Flower Blooms (2018).