Agreeing with Mary (
@Folly's place), from what I've heard the chicks need to have certain genetics to be accurately feather sexed. I think the genes were that of a slow feathering male and fast feathering female, but I can't really remember. But any breed (except
maybe silkies, frizzles, and frazzles) can be feather sexed as long as they have the appropriate genes.
I think the only way to figure out what genes your chicks have is to know their parents, but don't ask me anything beyond that! I'm not at all good with genetics. All I can tell you is that if they are from store or hatchery then as far as I know there is no way to know their genes.
You might find it interesting to read this:
https://www.backyardchickens.com/articles/an-experiment-in-chick-sexing-methods.72520/
Good luck!