This is what the YF-22, F-22's initial design looked like...and it was YF-22 that won even though the YF-23 looked more promising:
Notice the standard, F-18 type engine inlets and tail.
As i said earlier, what you see in J-31 today is not what it will be 10 years from now......these are prototypes for the initial production prototypes.
Here Nashir Gowadia....an Indian American who worked on the B2 bomber....a true stealth design....and ended up selling undisclosed amounts of research to the Swiss/Chinese/Israeli buyers.
Noshir Gowadia - Wikipedia, the free encyclopedia
Point being, we don't know how much of even the classified stuff got stolen and will end up in Russian/Chinese designs.