It's not simple, but it's not impossible.
The fact that she outzones him becomes irrelevant with the threat of teleport. OK, she can uppercut it, but if she starts to throw rings without thinking he will blow her up. Kung doesn't have to take any risks from full screen away, since she doesn't have a fast way in.
Yes, Sonya has armor, but he has it too, and he has a 6 frame launcher that will beat her if she starts being too predictable with her pokes/strings. So she has to be careful and respect spin.
Both of them have to take risks in this match. Remember, not everything Sonya does is safe.
It's not good for Lao, but not terrible either. If Sonya has an advantadge, it's a 5.5.4-5.