William Sadler, who plays President Matthew Ellis in Iron Man 3, reveals that he filmed a scene that was going to be in Ant-Man, but it was scrapped.
Peyton Reed's Ant-Man was supposed to have an Iron Man 3 Easter egg. The 2015 film wrapped up MCU's Phase 2 and was the first of the film series focusing on the shrinking hero played by Paul Rudd. In 2018, the sequel, Ant-Man and The Wasp
Ant-Man had a character-driven story with barely any connection to what's happening in the bigger MCU lore. Aside from the cameo from Sam Wilson/Falcon and the flashback opening that featured Howard Stark and Peggy Carter, the movie was focused on the new characters that it was introducing. Despite this, the film and its sequel ultimately played a big part in the Infinity Saga as the Quantum Realm was pivotal in Avengers: EndgameAnt-ManIron Man 3
Speaking with David Thompson and Thomas Carter for Lights, Thunder, Action!Iron Man 3Ant-Man
"I actually shot a thing for Ant-Man. I shot a bit of President Matthew Ellis for Ant-Man but they decided to use a different President, I don't know. It was pretty silly."
While Sadler didn't get into specifics about the sequence they filmed, what's more curious about his quote is that he said Ant-ManIron Man 3Agents of SHIELDCaptain America: The Winter SoldierAnt-Man
Regardless of what Marvel Studios was planning with Ellis' involvement in Ant-Man, the change of actor makes sense depending on how long the fictional president has already served in office. While the MCU's micro-continuity is confusing, the franchise still attempts to make sure that they have a cohesive timeline. For now, there's no word yet if Sadler will reprise his Marvel role in future films, but with the upcoming introduction of the real Mandarin in Shang-Chi and the Legend of the Ten RingsIron Man 3.