Do you have this reaction to just regular soy? Maybe try eating a bunch of soybeans and see if there's a similar reaction.
I have a friend who developed an allergy to soy and her reaction was acne. She found in researching it that it is an allergy that is becoming increasingly prominent. I don't think she cured it, she just eliminated all soy from her diet and her skin cleared up. I imagine an allergist would be able to provide more information/testing.