Following the immense success of The Super Mario Bros. Movie, Nintendo and Illuimation are reportedly developing not only sequels and spinoffs but adapting a whole other popular video franchise as well.
According to a reputable insider named Zippo (via Toonado), Nintendo and Illumination are collaborating yet again to develop another The Super Mario Bros. Movie, a direct sequel to the first movie. That's not much of a surprise given the box office numbers the animated movie accumulated. However, the supposed spinoffs are a bit more obscure.
Apparently, a movie focused on Donkey Kong is in the works in which Seth Rogen will presumably reprise the role of the great ape. Not to mention, one of the titular Mario Bros. is reportedly getting their own movie! There's a spinoff in the works starring Luigi, as played by Charlie Day in The Super Mario Bros. Movie, according to this scoop. It's speculated these spinoffs will take inspiration from the Donkey Kong Country and Luigi's Mansion video games.
Speaking of speculation, given the success of The Super Mario Bros. Movie, many figured that Nintendo would adapt more of their popular properties to the big screen and it seems that's exactly what they're doing. According to the insider, Nintendo and Illumination are developing an animated movie based on The Legend of Zelda video game series. What's more, it's said that Link will speak in this movie and it wont be a direct retelling of any The Legend of Zelda game in particular but rather an amalgamation of sorts.
Don't take these rumours too seriously, of course; though Zippo has had multiple Nintendo-related scoops in the past that were subsequently proven accurate, that doesn't mean their word is gospel. Not to mention, the WGA and SAG strikes that are currently going on are stirring things up as Nintendo and Universal were apparently aiming for a 2025 release for the aforementioned Donkey Kong spinoff and a 2026 release for The Super Mario Bros. Movie but those plans might be out the window now.