Lisa Lisa is DLC and Ermes is playable from the start. You gotta pay to be able to play with DLC characters (except Fugo, I believe), though downloading the campaign they're a part of lets you play against them at the very least.
From what I can tell they're releasing the DLC characters a couple at a time like they did in Japan, though I assume they're confirmed as they're all listed on the English-language website. Up to and including Baoh. The next Campaign is being released 15th May, check your calendars folks.
If the netcode weren't so appalling I'd be a lot happier, though trying to finish all of the Secret Missions in Story Mode, as well as getting all the Campaign medals is keeping me occupied. My Polnareff Eiffel is too stronk.