As a standalone, it's fine, just fine. It's interesting enough, plotwise, but the dialog is really difficult to listen to. It's so forced, and like someone wrote a boring, normal script, and replaced every six words with a fancy synonym they found in a thesaurus. Bloom's dialog especially is cringe-inducing and phony. Also, I wish the show was more colorful and fun, visually. I wish it didn't take itself so seriously. Overall, I don't hate it, and I probably will stick with it for the plot, which is captivating, but the dark, muddy visuals and mundane, dramatic dialog is a huge turn-off.
Also: I really feel like they did a disservice to Terra. I think they're relying completely on stereotypes for the token plus-size character by making her shy, sweet, anxious, and insecure. Not to mention, her costuming is frustrating. None of the characters have the glitz and sparkle that is Winx Club, but it feels like the designers went out of their way to make a beautiful actress look uncomfortable and insecure. It would be so much more empowering to see a confident and happy plus-size character who is seen as beautiful by other characters. Making Terra a timid and insecure character is a disservice to the message the show is trying to convey.