This feature request about a Moscow region.
This would be most, if not all of the actual Moscow/Capital region in real life ( I compared it with nearby regions, e.g. Amsterdam, London.)
The main airports would be:
Moscow Domedovo International
Moscow Sheremetyevo International
Moscow Vnukovo International
There are many other small airports and Air Force Bases around the region as well.
P.S. Sorry if this has already been requested, but nothing came up for it when I searched it.