Does CF EU/NA ETC.. need permission from CF CHINA to add stuff in the game?

Actually it's not for the permission. It's because all newer content is released on CF China because of the popularity and being the oldest CF Version alive. Smilegate HQ is located in Korea, and that is where the developers are. But not everything released in CF China will come to other versions. For an example, the new released Black Dragon weapons is currently CF West exclusive.