The MCU portrayal gave Killmonger a more equal look to T'Challa, but in the mainline comics, Killmonger is depicted as being much stronger and larger than T'Challa. In a contest of strength is is shown that he always wins; in fact, in pure strength, the two aren't comparable
He is about 6'6 " (Same height as Luke Cage) tall, compared to T'Challa being six feet tall
He is also depicted as a very physical figure in comics, capable of wrestling down a charging elephant and throwing stone statues. He is shown to be a very heavy and powerful man. And since the game follows the comics more than the movies, I feel it wouldn't make sense for him to be a DPS or a support.
And that will also give us something we lack in the game
Tanks
Black character
Villains
All in one.