Question: are the chitauri in endgame?
Answer: The Chitauri appear in Avengers: Endgame. They are shown in a flashback that took place during the events of The Avengers where some of them were shot down by the Ancient One. In the present, the Chitauri and their Leviathans are among the members of Thanos' army that the Nebula of the past brings to the present.