So here's a thing. Einstein didn't have trouble at school or start speaking until late.
It's odd that the myth that he didn't speak until four and struggled because he was dyslexic could have spread so widely. Maybe we all like to think that genius is shrouded in some way; it seems a bit unfair that someone could be as world-changing as Einstein without some sort of Achilles heel.
It seems (for better or worse), he was just flat bright.
Contrary to popular suggestions that he had struggled with early speech difficulties, the Albert Einstein Archives indicate he excelled at the first school that he attended. He was right-handed; there appears to be no evidence for the widespread popular belief that he was left-handed