Have you seen it? I didn't really like it, I would've preferred some closure - Otto's feedback for the demo and Brooklyn making a decision about going to acting school. She didn't mention it to Malibu. I wonder if they will have another falling out over it. If they do, I think they will overcome it and remain friends. Afterwards, I think either Brooklyn will go to acting school and The Barbies chapter of Malibu's life is over, with Brooklyn being written out or becoming long distance friends with Malibu... or Brooklyn will choose Malibu and her singing career over acting and they will stay friends and remain a singing duo.

I'll put up a spoiler warning here:

I would assume Brooklyn as a character will stay around, regardless of if she stays in California or goes back to New York. I mean, she's been hyped up a lot by Mattel (to the point of having her own birthday and being part of the logo for the YouTube channel), so I don't think she'd be written out.

A most likely scenario is that she'd still be involved in adventures, but we'd just see her more in her off time. Like, the beginning of "Barbie: Mermaid Power" shows the Barbies and Skipper, Stacie, and Chelsea all wearing swimsuits when cleaning up, indicating that they're in California. For as much as it's a sequel to Dolphin Magic, it also doesn't exactly require knowledge of Barbie It Takes Two to understand the plot. Any future movies would probably just be like that, establish at the beginning why Brooklyn is in California or Malibu is in New York, and then just do the adventure.