I don't think of The Masters as a professional tournament per se. It's more an invitational. They have a minimum of 6 invitations for amateurs, and theoretically the winners (or top finishers) of other tournaments with invitations could be amateurs.
https://www.augusta.com/masters/qualifications
Tiger Woods was doing really well at the Masters with an invitation as the US Amateur champion.
As for a women's Masters, I don't see it happening. There's only a limited amount of time (due to weather) where it's practical to have a tournament there, and the members want to be able to play there too when it's only open for half the year. Possibly a one-off event.