It seems the Chinese have duplicated PlanetSide and called it Welkin4591.
This is an English fansite for the game,
Welkin4591.com and I guess you can find the download on their wiki here,
Download Client & Patches | Welkin4591.com
From the video, though "beta", it looks like it is a long way from even getting close to surpasing PlanetSides inadequate coding.