http://www.china-defense.com/smf/index.php?topic=8229.540    (third post)

but I don't understand why the WS-15 (asssumed) nozzle doesn't seem to have any stealth features.The other nozzle seems to belong to WS-10B3 which, I think, is capable of thrust vectoring.

If this WS-15 is TV-capable, it must be done in a way different from that of the WS-10B3.