How many movies have Ayumi Horikawa and Tomokazu Seki collaborated on?

They have worked on 2 movies together! Their first movie together was Doraemon: Nobita's Treasure Island (2018) while their highest rated movie together was Doraemon: Nobita's New Dinosaur (2020). They have not worked together since Doraemon: Nobita's New Dinosaur (2020).