Hypatia

It's not just TVC though, the WS-15 also has >25% more thrust than the WS-10C that most of the J-20's currently in service are using. It's meant to provide supercruise capability, I don't think that kind of performance is too much of a stretch.

The flight performance is probably just because it's the J-20A with the thrust-vectoring WS-15 engine, which iirc isn't in full service yet IRL. That said, the RCS is definitely a little overtuned; I tried a BVR fight with it and Grinnelli's F-22A and neither of us could even detect each other on radar until about ~10nm, which strikes me as a bit much.