I didn't see any male rump feathering in the close up, so I'd guess it's a hen. Some hens have more typically male neck feathering, plenty of mine do, and some even have the curved rump feathers. Unless it does a number like that male of mine did, I'd guess it's a girl. Mine looked even more of a girl for even longer. But it was an exception.
About gender appearance swapping, it's possible that one I had was female, but it always had a more male shape to it even though for all the signs I thought it was female. I suspect it may have just had low and late-starting hormone issues. I have had some hens mate with others, but none of them were masculinzed. I wonder if, at some time in the past or even for some small percentage, a successful gender swap is possible. Like those fish that change gender once or even multiple times in their lives.