Oh man, this is complicated and since such a huge portion of Africa was involved and different African countries have different historical memories nothing is uniform, but still a great question worthy of some sustained analysis.

I'm mostly familiar with the Senegalese and Ghanaian cultural memories. These nations have engaged in high level outreach to the descendants of enslaved people in the Americas in order to engage in healing and cross cultural dialog. In 1993, the association of Ghanaian tribal chiefs sent a high level delegation to the United States to apologize for African complicity in the transcontinental slave trade in a series of high profile public events. The Senegalese and Ghanaian governments have actively preserved many of the slave forts as sites for historic interpretation and have tried to partners with American institutions to help tell this story. While it is a major topic, for most African people in nations effected by the slave trade, the more immediate issue is the legacy of colonialism, which is something that happened so much closer to today.

I hope this helps a little bit; My knowledge on this comes mostly from my work as a phd student studying the American side of slavery in the 19th century and as a park ranger at the African burial ground national monument in manhattan.

My parents are from Nigeria. I remember my dad saying when he was in school he didn't really learn a lot about the slave trade because it's not a significant part of Nigerian history. He was surprised that its always mentioned in the US