Both spellings are legit in Wales.
Bronwyn with a "y" is the male spelling and Bronwen with an "e" is the female version.
Unfortunately, I'm seeing a lot of North Americans not following the gender rules of the Welsh culture. It's one of my pet peeves. If you're going to appropriate a name from a specific culture that isn't your own, people should respect that culture when it comes to spelling and pronunciation.
I don't know anyone with the name.