@ Sebor: I'm pretty sure that Eddo is right here, the Chinese answer to T-51b was the stealth suit. ( I think. )
You are wrong and Sebor is right.
China created Stealth Suit. America used captured Chinese tech to create Stealth Boys
T-51b Power Armour was created as a replacement for T-45d power armour. Power Armour was created to better protect troops on the battlefield and make people walking tanks.
The Chinese Stealth Suit and T-51b PA are not related. They were not created to counter one another at all.
T-51b power armour lore wise and as seen in the Originals would crush someone in a stealth suit.
Edit: If by somehow the Chinese Stealth suit was a counter to T-51b power armour (which it wasn't) it failed miserably. America was able to retake Alaska and invade China itself. American forces using T-51b power armour made it all the way to the heart of China, the Yangtze River.