Sorry, this new Link is a guy. That's just how it is.
I'm honestly going to doubt Nintendo would make their first female Link flat chested.
I'm not talking about giving Link double-d's, either (if you actually read my other posts, you would know that, but I guess I shouldn't expect that from you now).
Nintendo has a history of giving their older female Zelda characters tits (show me one that doesn't have them. and no, Sheik doesn't count, since she was Zelda, and she obviously wrapped those boobs down heavily... and female Link would have zero reason to do that herself, unless it's illegal to be a woman in Hyrule), and they're not going to stop with the first female Link and go all like "OMG flat chest." So, you know, it just is how it is.