To be honest, this is definitely not hyper-masculine. There are other images in which Sun Jing is dressed more masculine, but this ain't even anything near hyper-masculine. (See http://dynasty-scans.com/images/2835)
Additionally, a tomboy is just a girl that likes to "roughhouse with other boys". It's a description based on behavior, not on looks. So even the most femme of femmes could be a tomboy.
And side note, this looks more like a pixie cut, which plenty of women, from all over the spectrum rock. :)