Kevin Feige and Marvel Studios have learned a lot over the years, specifically with how they handled Avengers: Age of Ultron. This time around, instead of ending each phase with an Avengers movie, Marvel made it a point to make these movies a way to cap off each saga - not phase. Case in point, Avengers: The Kang Dynasty and Avengers: Secret Wars, which premieres on May 5, 2025, and May 1, 2026, respectively, will be the only Avengers film for the Multiverse Saga. But, while the gist of the former is pretty self-explanatory, the latter is a huge question mark, and a leaker claims to know what Marvel plans to do to make sure it isn't a "4 hour movie".

This is how they plan to make Secret Wars work without making it a 4 hour movie.
Kang Dynasty will have the "New Avengers" as the leads. While Secret Wars will mostly be from the point of view and will focus on the heroes from the other universes.
— MyTimeToShineHello (@MyTimeToShineH) January 1, 2023
According to @MyTimeToShineHello, Kang Dynasty will feature Anthony Mackie's Captain America as the leader of the new Avengers team, who will face off against Jonathan Majors' Kang the Conqueror. Although this isn't somewhat surprising - some are even expecting an Infinity War-like plot where the newly-assembled team of Earth's Mightiest Heroes end up losing - what comes next is quite interesting.
The trusted insider adds that the "Secret Wars will mostly be from the point of view and will focus on the heroes from the other universes." They add that some of the heroes expected to appear in Secret Wars are Tobey Maguire's Spider-Man and Hugh Jackman's Wolverine, with some also speculating that Robert Downey Jr's Iron Man will be a part of the mix as well.
A way this could happen is Kang Dynasty ending on a cliffhanger as the multiverse opens to let legacy heroes and villains into the battle world. Seeing as the Beyonder, which the MCU will reportedly introduce as a different Kang variant, will serve as the villain of Secret Wars, what the leaker is saying could end up being true.
Of course, this is all speculation at this point. This could very well be the initial draft of the story of Secret Wars, but until the movie premieres and we're able to watch it, we can't say for sure this is what will happen.
Keep in mind that Marvel Studios isn't afraid to change plans mid-way. For example, Balder the Brave was supposedly part of the Illuminati in Doctor Strange and the Multiverse of Madness and he was nowhere to be seen. Also, the original plot of Black Panther: Wakanda Forever was going to be different before the untimely passing of Chadwick Boseman. So, until the credits roll on Secret Wars, all we can do is wait.
We'd have to admit though, we're pretty excited to find out more about what's in store for the MCU.
For now, we'll have to "settle" with the beginning of Phase 5 with Ant-Man and the Wasp: Quantumania on February 17.