According to the source:
A Kirby movie is in early development.
It is also claimed that a Donkey Kong movie is in advanced development with a release in 2028, and the third part of the Mario movie is allegedly planned for 2029.
Other projects mentioned include Star Fox, targeting 2030, as well as Luigi’s Mansion and Yoshi’s Island in early discussion stages.
The source also stated that “despite previous statements, a Super Smash Bros. movie is in the works, but will only be released after Star Fox,” adding that ideas for movies about Bowser and the Peach and Rosalina duo are being considered.
Nintendo has not officially confirmed new projects.