Look, this is one of those direct-to-video Barbie movies that Mattel churned out by the dozen in the 2010s. It's perfectly safe—you could leave your 5-year-old with this and nothing bad would happen—but it's also just... not good.
The 5.7 IMDb rating and 67% audience score tell the real story: even little kids find this one kind of meh. The animation is stiff, the story is predictable, and it feels like a 75-minute toy commercial (because it is). If your kid is obsessed with both Barbie AND ballet, sure, they might enjoy it once. But you're not missing anything if you skip it.
The 2023 Greta Gerwig Barbie movie has kind of ruined these old direct-to-video entries—once you've seen what Barbie content can actually be, it's hard to go back to this stuff. If you want ballet content for little kids, try Angelina Ballerina or even Leap! instead.