Pretty much what @
Drizzle and @
EMPEROR_SunFire said. Its knowing the MUs and knowing when to utilize ji3, air dashes, blocking then dashing, IADM, and in the right range, Amazonian Smash. Also to pay attention to their meter and what it's used for. Like someone like Sinestro for example. If he shoots a FB and has no meter to spend, its a guaranteed dash, and then some. If he does have meter, simply just wait for his short window to delay MB passes and that's when you'd move in.
If you wanna get technical, WW's full dash, as in duration with recovery, is only 18f. Anything that's at least -12 on block, will guarantee a dash forward. That, or anything where's there is an 18f gap between two different hits. Such as for example (solely an example), the hit you with a projectile that's +8, the fastest move that they can throw out to catch you from a distance has to be at slowest 26f, so you should be able to always dash forward and block right on time even though they were plus. But yeah, all in all, it's knowing the MUs