If you recall, WWE has confirmed that the following WWE superstars will appear on the RAW brand in the cruiserweight division. Gran Metalik, Akira Tozawa, Jack Gallagher, Johnny Gargano, Tommaso Ciampa, Cedric Alexander, Rich Swann, Brian Kendrick, Noam Dar and TJ Perkins.
For now, this appears to be the entire roster according to PWInsider. It's just going to feature 10 superstars, but it's likely possible that new cruiserweights will be introduced over the coming weeks.
The current plan is to have the RAW cruiserweights to work RAW TV events as well as NXT TV events, and even NXT live events. They'll likely start working RAW live events soon as well, perhaps.
The division kicks off September 19th at RAW in Memphis.