If the MSFS CRJ is like the P3D version, it will probably come with its own AIRAC database that is independent of the sim.
With new aircraft releases, Aerosoft usually supplies a free copy of their own NavDataPro AIRAC specific to the aircraft, which would normally be the cycle current for the release date. If you wanted to keep it current once the initial AIRAC expires, you would have to subscribe either to NavDataPro (from Aerosoft), or Navigraph who (I assume) will make a database for the MSFS CRJ, since they already have a compatible one for the existing P3D version.