If your question is, how to counter with the counter? ==> When two player use the counter around the same time, the time will go slower for a bit as you see, there isn't anything that can be done by then. Who did it as last will attack, the first one will be punished. The slowmotion isn't a fast thing to react or something, it is just a effect. Pro fighter don't use the counter very often, so the slowmo rarely accours there.