Most would say Wing Chun.
I would say Pi Gua or Tong Bei.
There are extreme flexibility requirements around shoulder, back and chest for Pi Gua/Tong Bei.
I was able to have some flexibility when I was in high school.
I had tough time to drill the moves when I was in college or fully grown.
As I age, the flexibility drills just got harder and harder.
What do you think?
Of course, all styles can be done moderately or in smaller ranges for girls.
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