Jesse, I've just looked over my notes on the Atlanta Campaign and can find no references to a woman leading Confederate charges; I admit that most of my notes reference the Union side of the aisle. In all honesty I think it a bit unlikely as casualties among
CSA line officers were quite heavy at Peachtree Creek and for a woman to be in the line of fire let alone leading several charges like that would be less than healthy, I don't think Hood, or many of his officers would have allowed it. The sheer dishonor to an officer who allowed a woman to lead a charge instead of him would be prohibitive. Not to mention the ribing that would have been received from the Union troops. The costume you mention would have been noticed I'm certain, especially as those western boys had a nasty tendency of picking off anyone riding a horse on the theory that "if I'm walking then by god they ought to be."
Intriguing story, I'll continue to go through my notes. I believe my local Historical society has a copy of Hoods memoirs, I'll take a look see this weekend.