Usually the way how it happened was African chiefs and kings would sell their captives or slaves to European traders for profit, these slaves who were sold however were not of the same ethnicity as the African leader or trader selling them nor did they identify with them, the slaves sold were primarily war captives. The trans-Atlantic slave trade happened like all other slave trades around the world. Traders come and trade in slaves who were previously captives and sell them. Back then people did not have the same morals as we do today, hence why slavery was so common and normal in the old world, from the Roman enslavement of Germanic ppls and those of different ethnicities close in proximity to Rome to the muslim enslavement of Slavic and Turkic people. Slavery was a legal and tolerated practise 100s of years back and no one really had much problems with it, I know it sounds messed up but that’s why you should not moralise or idealise history.

But to cut it short, there was no “tricking Africans” into selling slaves, Africans are not a monolith so it is inaccurate to portray them as “selling their own people”, this is why again you shouldn’t moralise or idealise history or fit it to suit a certain narrative. The African ethnic groups obviously knew full well what they were doing and sold slaves for profit. There is really not a complex issue, but however note that this was not exclusive to Africans since all other slave trades started because of profit and nothing more.