(last updated: 12/28/17)
Guilty Gear's setting occurs in the distant future, after a 100 year war during which Gears went wild and fought the humans. It was called the Crusades. However, in current continuity, that war never happened. Japan is still in one piece, and the Japanese have not been locked in protected colonies. This affects several characters in Guilty Gear's theme, such as Baiken, who will have to have lost her arm in a different event entirely.
Most of the characters will transit readily into theme as earlier versions of themselves; the Sacred Order was in this theme established as a reaction to the fighting community and the likes of Shadaloo and NESTS, not the Gears. However, some characters, such as ones attached to the Post War Administration Bureau, will regrettably not exist.
Some characters from the Guilty Gear series are not appable. JUSTICE is a TP character and cannot be applied for. Because Justice has not yet made an appearance in game theme, this also means that DIZZY is not appable.
WARNING! Only the characters from the first Guilty Gear, Guilty Gear X, and Guilty Gear XX games are appable at current.
More will be created, opened, and subsequently released when they are unlocked. :)