I know a Mawgan, which is Cornish - I assume it's a place name (Mawgan Porth) used as a Christian name.
Mawgan seems a bit less.... eighties American sitcom actress?.... than Morgan to me, and therefore nicer. But I am undoubtably a terrible snob possibly a bit picky about these things.
I believe that strictly it's a boys name, but the one I know is female.