Most of the images/info coming out right now are either from Arcadia magazine or from pics people are taking while they're at the loketest areas. The only Tsubaki stuff in the original game were from the story mode (pretty sure at least).
she's being added to the newly updated version of blazblue. Its supposed to have new moves, rebalancing, some additional storyline, and 2 new characters. tsubaki is one of them