I won't delve too much into the aesthetics because that's been covered quite a lot in the media (essentially the sartorial elements are homages to fashion from across the continent). But here are the other things I noticed.
Cultural references:
When Kilmonger says the sun will never set on the Wakandan empire, that's a direct reference to the same oft-quoted saying about how the sun never set on the British empire in its heyday.
Most of the dialect was constructed using Xhosa and other southern African languages as a reference point. But Winston Duke, who plays M'Baku studied Igbo (a Nigerian language) patterns to devise his accent. He even ends some of his sentences with sha, which is a very Nigerian thing to say, haha.
Even the name of Winston Duke's tribe, the Jabari, is a Swahili word for 'brave'.
At the beginning of the film, Lupita Nyongo who is conducting a mission to rescue some girls is actually speaking Hausa, a Northern Nigerian language. She only speaks it for a few lines to some of the captives and then for the rest of the film either speaks Xhosa or English. But it's pretty clear what that scene is referencing.
T'Challa's all-female royal guard, the Dora Milaje, mirrors the Dahomey Amazons, who were an all-female regiment in Benin, all the way till the 19th Century.
This one was probably obvious, but the Wakandans worship Bast, an Egyptian cat god.
Again, another really obvious one, but the hairstyles in the films often reference traditional African hairstyles like braided plaits with wax, dreadlocks, Fulani braids, to even the high top fade with twists...occasionally known as the 'thot boy haircut'. For what it's worth, that's my current hairstyle.
OK, I said I wouldn't delve too much into the fashion of the movie, but some of the scenes in the capital city in Wakanda are probably inspired by the Congo Dandy or La Sepe movement, which is a fashion movement prevalent in the Congo, but which has spread to other parts of Africa as well. Essentially people dress in a way inspired by European colonists but add a more colourful flair to the look. It's not a huge element of the film, it's just something that you can see in the background and in Isaach De Bankole's character who wears an emerald suit. He's the man with the lip plate in his mouth.
Many of the symbols in the film are Adinkra. For those who don't know, adinkra are essentially pre-colonial symbols used in West Africa that represent symbols or ideas. There has been some debate, mostly online from what I can see, whether it constitutes a written language or is more symbolic. In any case, W'Kabi has quite a few on her blanket and I think a few are on the Wakandan architecture.
Weapons/Martial arts:
During T'Challa's first ritual fight scene, when he switches to hand to hand combat he uses a style very similar to capoeira. Although this might be seen as anachronistic, as capoeira is thought of as a Brazilian martial art, it actually originated in Angola and spread throughout the African diaspora via the slave trade. For example, in Martinique, a small island in the Caribbean, they practice Ay'Ga, also known as Ladja and Danmye, a very similar martial art that I believe is dying out. EDIT: There aren't a lot of English language references to this martial art online, but I found a wonderful Library of Congress video from 1936 depicting the art. And at the risk of leading down an unrelated rabbit hole, this footage was filmed by the acclaimed dancer Katherine Dunham, who is known as one of the most important figures in dance history. Well worth researching her as well.
Many of the weapons used are pre-colonial weapons used by several African kingdoms or tribes (with added vibranium of course!). More obviously are the Zulu assegai/iklwa (short stabbing spear) and isihlangu (shield). But if you look closely during other fight scenes you can see other weapons that are either entirely based on, or heavily inspired by traditional African weapons. For instance: a khopesh (an Egyptian sword), shotel (Ethiopian sword) and I believe Michael B Jordan carried a sword that mostly references the Genya short sword from the Kongo. In terms of non-stabbing weapons, they feature a few clubs probably inspired by southern African iwisa and a few East African clubs too.
EDIT: I'm terrible at formatting. And I also thought of other things.