Hillary, Stacey, Shannon and Ashley were all originally men's names in English (Shannon derives from Gaelic). Once a critical mass of women start appearing with a man's name, people stop naming their sons those names. Johnny Cash songs aside, it doesn't go in the other direction.
All the "Trey" named men I know are actually some sort of Firstname Lastname III, and their families start calling them Trey to not confuse them with their father and grandfather. They have also all either been Old Money or complete hillbillies.
The current terrible naming trend for women is giving them a patronym as a first name, like Madison, which literally means the son of Maud (another male to female crossover name).
All the "Trey" named men I know are actually some sort of Firstname Lastname III, and their families start calling them Trey to not confuse them with their father and grandfather. They have also all either been Old Money or complete hillbillies.
The current terrible naming trend for women is giving them a patronym as a first name, like Madison, which literally means the son of Maud (another male to female crossover name).