Claws of Awaji is officially said to
contain around 10+ hours of additional content, with a new weapon type, skills, gear and abilities also coming to the game.
In addition to the Claws of Awaji DLC, sources tell me that
Shadows upcoming co-op mode, currently codenamed 'LEAGUE' is still in development and intended to release sometime next year.
Previously, I had presumed that the co-op mode will allow you to play as Naoe and Yasuke to fight side-by-side, however, I'm told that this isn't entirely accurate. One source said that "while they're obviously central characters, there's a deeper narrative tied into the co-op that will expand the experience beyond just the two of them."
So, presumably, you'll be able to play as more than just Naoe and Yasuke.