Guarantee is probably a strong word, but consider that Rosalina is very popular and has been making appearances even beyond the spinoffs (Getting into 3D World as a post-world character, being the only 8-bit character secret aside from Mario & Peach in Odyssey, etc.). It's only the RPGs she hasn't really appeared yet and that's probably due to story issues. Even then, the RPGs generally don't follow what the platformers and their immediate spinoffs do (at least, until recently) and vice versa.Shadowshy said:wrongThatGuy62 said:It's all about roles my man.Mister Wu said:To be fair, Rosalina is more likely than the Koopalings and, if Odyssey teaches us something, even Bowser Jr....
anyway less likely than the Little Birds
Even if Rosalina doesn't get a large one, she's still guaranteed to cameo.
It would be extremely easy to make Rosalina and the Lumas the post-credits scene.