A major MCU theory suggests that Tobey Maguire and Andrew Garfield's prospective returns in Avengers: Secret Wars were already set up in Phase 4's Spider-Man: No Way Home. After debuting as different versions of Peter Parker in 2002's Spider-Man and 2012's The Amazing Spider-Man, respectively, Tobey Maguire and Andrew Garfield reprised their roles alongside Tom Holland in 2021's Spider-Man: No Way Home. Their reappearances in live-action sparked speculation that the pair could return to the role of Spider-Man more times in the MCU's future, specifically in 2027's Avengers: Secret Wars, which is expected to feature cameos from several previous Marvel actors, both from the MCU's past and other live-action franchises.
https://screenrant.com/avengers-6-spider-man-maguire-garfield-returns-secret-wars-theory/