Earlier today came the news of a brand new Marvel rumor from The DisInsider that characters from the hit Big Hero 6 franchise could be making their way to Marvel Cinematic Universe in some form. Which characters this will be and where they'll appear is still up in the air for the time being according to the site, but Marvel fans with exceptional memories will no doubt recall that the MCU has already set up the arrival of these characters in a subtle way. Back in 2015's Avengers: Age of Ultron, Tony sifts through a series of AI programs he has lying around featuring a few different easter eggs including J.A.C.O.S.T.A., a female robot created by Ultron in Marvel comics, and also T.A.D.A.S.H.I., seemingly a reference to Hiro Hamada's older brother.
As you also may recall, the animated film Big Hero 6 was loosely based on the comic book miniseries of the same name from writer Scott Lobdell and artist Gus Vasquez. Though a Marvel property, following the success of that movie and its animated series spin-off it seemed unlikely that Marvel Studios was ever going to use them, having been remade into the image of something unique and new by Disney Animation. Now however, as The DisInsider notes, Baymax and Hiro are probable candidates to appear in the MCU at some point, and though the above was clearly just an Easter egg (or happy accident, seen below) but will no doubt be retconned into connectivity.
It's unclear where the Big Hero 6 characters could be appearing, but the site reports that in-development Disney+ series Secret Invasion, the upcoming Doctor Strange in the Multiverse of Madness, or even an Agents of Atlas project could be potential landing sites. Furthermore it remains to be seen if the version of the characters that appears in the MCU will be influenced more by the ones seen in the Disney animated film, the Marvel comics series, or some kind of amalgamation of both.
The 2014 Big Hero 6 animated film brought in over $650 million at the global box office and brought home the Best Animated Feature Oscar to Walt Disney. The film went on to spawn a television series, Big Hero 6: The Series, which aired for three seasons on Disney XD. That series, which saw much of its movie cast reprise their roles, aired its final episode on February 15th. A spinoff series, Baymax!, was announced during Disney's Investor Day back in December and is scheduled to debut on Disney+ in 2022.