Ekranoplan Casspian The Russian Tank-Ship-Plane. Not exactly a plane but still cool. It flies just over the water because of ground effect. So it can haul a heavy load very efficiently compared to getting it up to altitude. Or floating.
Chinese Stealth Tech- many think China borrowed fighter technology. I also think it would be foolish not to use proven ideas. Plus if your designs can be taken the only main advantages are strategy and training. This where the majors have the edge.