I have said this before, but in order to do a Fallout game set in another country and do it right, you really need a development staff that is deeply invested in that country and its lore. We would not be playing a game about China, we would be playing a game about preconceived notions that Americans have about China. It might be enjoyable to play, but the Chinese players would probably roll their eyes at just about everything in game.
Hell, take a look at Canada. That country and its citizens are about as close as you can get to the US and its citizens culturally, but there is no way US developers could accurately depicted Canada in the Fallout universe (or vise-versa). That would require Canadian developers to properly do a Fallout game set in Canada. (Of course, it might be possible to do a Canada themed Fallout now considering the new office Bethesda just opened).