The Winx Club and Fate: The Winx Saga is that the latter live-action series is edgier and aimed at older teens and young adults.
It's like how the Dark Knight movies decided that Batman should be super serious and gritty. You could drive yourself crazy listing all of the little differences between the live-action show and the cartoon.
Bloom meets Stella in the park, not in the dormitory. Why don't they all have wings? Where's the rabbit? Etc. So here are the major differences worth mentioning.
On the Netflix series, Stella is a known princess and Bloom like... might have royal roots. But on the Nickelodeon series, all of the Winx are fairy princesses, including Aisha and Musa.
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