It seems like she has audio cues that can help figure out which one is which. And along with this, if you notice her 2A+G has a short windup before she slams her sword into the ground, whereas the 2B+K shows her immediately stabbing it into the floor. It is just barely different but we will have...
The deluxe version includes the season pass for the DLC. I don't think it comes with any additional art or pre-order bonus, from what the Steam page says.