Back in 2014, Nintendo partnered with Koei Tecmo (specifically the Omega Force division) to create Hyrule Warriors. The collaborative project features the gameplay of Dynasty Warriors blended with the world, characters, and weapons of Nintendo's Zelda franchise. Hyrule Warriors has been a big success, and Koei Tecmo has expressed interest in creating similar games with franchises like Mario and Pokémon.
While no other Nintendo Warriors projects have been announced yet, one was reportedly pitched to Nintendo. According to the latest report from Laura Kate Dale of Let's Play Video Games, Koei Tecmo pitched the idea of a Star Fox Warriors game to Nintendo early in 2016. The game would have focused on melee combat (like other Warriors games) between characters from the Star Fox universe, but there would also be also be space missions with simple controls and "over the top" visuals.
Nintendo ultimately rejected the pitch due to questions regarding the future of the brand. However, Koei Tecmo is still interested in working with Nintendo on another Warriors title, and Nintendo is reportedly open to the possibility.
This information is not officially confirmed by Nintendo at this time, but Dale has sources at Nintendo who have proven accurate in the past. Additionally, Liam Robertson (known for digging up details on cancelled game projects for Unseen64) has since corroborated this report. Robertson heard of this Star Fox Warriors pitch from the same source that tipped him off to the existence of an unlisted Hyrule Warriors Legends trailer before the game's official reveal.