According to Charles Pulliam Moore at io9, there’s a good reason there are a variety of “Wakandan” accents in the new Black Panther movie. Pragmatically, it’s because the cast comes from a variety of backgrounds and couldn’t help but bring their native idiolect into their respective roles. Beth McGuire, the dialect coach on the film, does a great job of explaining that at the linked article.

But there’s also an in-story explanation that actually makes some sense:

In both Marvel’s comics and movies, a significant part of the lore about Wakanda focuses on the fact that the country was never colonized—something that might make one assume there would be a singular Wakandan accent. But because the MCU’s depiction of Wakanda is so deeply rooted in much of the iconography and traditions of real-world African cultures, it makes sense that there would be a multiplicity of accents.

What’s more, Black Panther actually goes out of its way to emphasize the fact that modern-day Wakanda began as a coalition of multiple tribes who seized the opportunity to unite and grow together around the impact site of the vibranium mound. Respect for tradition and history is a central element to the MCU’s Wakandan society, and it stands to reason that the different accents unique to each tribe would still very much be a part of modern Wakanda.

So, linguistics and superheroes! Yay!