How many movies have Iseki Keiko and Kôsei Amano collaborated on?

They have worked on 1 movie together! Their first movie together was Sailor Moon - The Legend of Kaguya Island (Revision) - Summer Vacation! The Jewel Expedition Team (1999) and was their highest rated movie together. They have not worked together since Sailor Moon - The Legend of Kaguya Island (Revision) - Summer Vacation! The Jewel Expedition Team (1999).