Given the NEO has only recently rolled out the hangar door it’s pretty cool to think we can already fly a simulated version right now. There are two options available to the simmer at present, no doubt these will receive service packs over time once the real world performance figures and cosmetic details settle in as the aircraft approaches delivery and enters service with clients. All of these are running a CFM56 engine but the initial production release of the NEO appears to be a P&W powered machine so re-engining is on the cards too.
The other players potentially with NEOs in the works I assume will be Blackbox Simulations and their AirbusXtreme and the FlightSimLabs A320 which has yet to see the light of day but promises to be nicely done given their track record.