There are so much exaggeration about the Chinese military tecnology.I would not be surprised at all if war broke out today you would see some sort of PRC stealth fighter deployed and fighting now.
I would imagine it would take the form of some twin engine, radar absorbing covered, mixture of both passive and active stealth features in the form of a J-10 type airframe.
Would not take much to have something stealthy, at night and in such a cluttered battle-space such as the Taiwan straits would be very hard to make good contact and identification depending on who is looking.
Remember there is going to be more radar contacts be it surface or air contacts than any American or for that matter RoC information collating systems can handle. Not to mention ECM dedicated aircraft throwing wrenches into the battle management system
China high tech industrial base remain weak,all of the current weapon system such as J-10 ,yuan class submarine,aerospace engine...etc has outside input,particular from russia.