For Leifang, you stun them with 6P+K and then use a neutral throw. This makes you -3 and players may try to punish you for the throw that whiffed, getting you a free conter throw or hicounter strike. I have yet to really test it against other people. Momiji's version is similar but you just deep stun them and use 41236T, it doesn't make you -3 consistently.
Oh that, I think other characters can do that too, like Naotora and Kasumi can do 6P on counter hit for that same result. But then again a strike beating a hold does result in hi counter hits
That's known as a ''safe throw setup''. The way it works is that makes the advantage from big stuns more manageable, allowing for better frame traps and hold punishment. Pretty much everyone can do it since jab stuns are so good in this game, but characters with deep stuns have it best, especially grapplers, their throw speed makes them able to get better results even on opponents who stagger escape fast.