There is an Outletcenter in Salzburg now. But i have never been. Between Salzburg and Munich there is nothing really. The only Mall that comes to my mind is also the RiemArcaden. It's right off the A99/A94.

We do not use these terms but i assue your E5x is the A8 from Salzburg and the the other E is the A92.

Maybe you can tell us what you want to shop - then we might be more helpful.