Tutu Effect
The Tutu Effect: n. The phenomenon of misremembering the Mandela Effect, named after Archbishop Desmond Tutu, who many people falsely remember as being Nelson Mandela. This is often caused by confusing the two prominent South African leaders who were active during the anti-apartheid movement. Can also refer to misremembering details about other events or people that are similar in nature. Additionally, it can also refer to meta-irony, where people recognize that they are having a 'Tutu Effect' moment.
I was convinced that Charlize Theron was in the movie 'Aeon Flux' but my friend corrected me and said it was actually Margot Robbie. I must have fallen victim to the Tutu Effect.