Who was Brightons first black player?
David Busby
I think you may find it was Denis Foreman.
https://en.wikipedia.org/wiki/Denis_Foreman
Edit: Dunno where the Busby story is from. Denis was 'Cape Coloured' (which meant blick, in Sart Efrika, at the time). I used to play knock about football with his boys, Kevin and Michael, in Easthill Park, in the late 60s and early 70s.
You could always send Paul Barber, correcting the mistakeWebsite says it is Busby (https://www.brightonandhovealbion.com/news/2275182/black-history-month-proud-to-be-albion) but you appear to be right.