www.snopes.com/fact-check/jk-rowling-transphobia-transgender/
Snopes have written an article which, to be fair, does say that the claim on a Medium post that JK Rowling has 'confirmed her antipathy towards trans women' is false. But then it goes on to say that, on the other hand,
"Rowling has never articulated solidarity for trans people or support for trans rights or trans inclusion. A search of Rowling’s Twitter feed showed that she had never once used any of the following terms: “trans,” “transgender,” “LGBT,” “LGBTQ,” “transphobia,” “transphobe,” “transphobic,” “TERF,” “inclusion,” or “exclusion.” Though they are not necessarily indicative of her views, and certainly not definitive proof, these absences are certainly worth noting."
So Ms Rowling. We've noticed that you've never done any witch-hunting. Which is suspicious. Highly suspicious.