The Winkleman Effect

/ðə ˈwɪŋklmæn ɪˈfɛkt/
noun.
Also known as the Robbie-Mackey Effect. The misplaced belief that two or more unrelated celebrities are the same person based on the fact they have shared physical characteristics or near identical appearance. Named after British TV presenters Claudia Winkleman, Anna Richardson and Davina McCall for having the same dark brown bob haircut and getting mistaken for each other.

Person A: Jaime Pressly, Samara Weaving, Margot Robbie and Emma Mackey all lookalike! I thought they were one really talented and busy person!
Person B: Nah, it’s just the Winkleman Effect.