Su-35 F-15EX F-16V typhoon are typical 4.54.5, not 4, they already have the characteristics of 5th gen like the overall shape, ram coating or sensors. And J-20 has already flown with WS-15, their new 5th gen engine, and if I remember it right, the engine is in serial production.
F-22 is typical 5th
There are F35 Su57 J20 Kaan between them.
F35 is because lack supersonic cruise ability .