Fiddling around with different skin tones and facial structures, these are my versions!
K. Rool is an african crocodile, so I kept the ethnicity of his species the same.
Bowser is of an asian background, due to his castle representing traditional asian architecture in Odyssey.
Dedede is... I have no clue. He's a giant blue penguin. Let's assume since his universe is based around space that he's an extraterrestrial. Like Starfire, who has vibrant orange skin and bright pink hair.
King Wart/Mamu is Arabic like the protagonists of his original game, Yume Kōjō: Doki Doki Panic.
For a long while I've been planning out this story that could serve as a sequel to the Kirby anime, and this is the cover image for the first stretch of the story (the first chapter or so).