My only possible issue with a Black Panther AAA open world game set entirely (or mostly) in Wakanda is the potential to erode at the idea that it's basically a utopia. Video games like Spiderman and Witcher require constant conflict and beating up on criminals, monsters, etc. It's not great for the overall image of the kingdom to seem plagued by those issues unless a compelling explanation is given explaining why T'Challa is dealing with them 24/7. Otherwise Wakanda comes off looking less like this idyllic African civilization and more like an afrofuturistic version of Gotham or Night City.
It's more than possible to provide that explanation, I just would hope that developers keep that at the forefront of their minds rather than have stuff like missions where you gotta shut down a network of sci-fi rape camps lol. Wakanda's history as an isolated warrior culture with an exceedingly high quality of life means you gotta get creative with the domestic threats without contradicting the core aspects of the mythos.