Would you say that's her 2A or her 6A smash attack?

I'm not well versed with attacks or whatever... You make this while on run, just press Z. This attack is probably the best reason I like playing Alice. When you kick your enemy constantly, you look like gangsta -w-

That's her 6B. Animation for both still and running is mostly the same.

This is an Earthbound reference, not a Smash reference. Earthbound gives you "Smaaaaash!!" when you land a critical hit.