[Edges]

If it was a specific limitation that went on a specific trait, you just multiply the value of the limitation by the value of the trait and count that as a disadvantage being given by the affliction.

If it is a specific limitation that can be applied to any trait, you would have to build something along the lines of modular abilities or wild talent. Alternately, I might just eye-ball it as each -5% counts as 15 points of disadvantages being imparted through affliction. That is inspired by wild card skills costing triple what the hardest skill costs. In this case, a "wild card" limitation affliction could cost 3x what the limitation would be on a 100-point trait. YMMV