I'm nowhere near the level of these other guys but from what I've seen with the 9/13 ema they can cross during W2 and W4 if they are longer waves and also after the completion of a sequence too. I would suggest doing a wave count on multiple time frames and see where it's at. You also need to settle on a method for trading that works for you. The count is important here because you don't want to be selling at say the bottom of W4 if you've already rode it down and then buy back halfway up W5.
A quick look at STX to me looks like it might be in W4 on the weekly scale, and likely in the B or just finished the B wave of the ABC as you've stated above.
If you are using the weekly for your count, the ABC correction will be clearer on the immediate scale down (daily).
