what is graphic engine? Unreal Engine 4?
You can use any engine you like for rendering. As I can see it now, out-of-the-box Chimera is going to supply tools to build on top of Unity3D framework, but nothings holds (aside from lack of free time) to build Unreal Engine 4 plugin as well.
i mean that, is it possible to make a decentralized mmorpg game like; blade&soul,blackdesert online or worldofwarcraft etc. with cool graphics? those mmos hosting game to server, players connect the server with clients...