Dline questions in nickel 3-3 formation

i like to run nickel 33  as my base defense and I’m looking for some advice regarding the dline out of this formation. 
Im using tommie Harris at dt with inside stuff and secure tackler , chase young at re with no outsiders, and Barmore at le with no outsiders and inside stuff on run downs.  in passing situations Il put parsons at re with edge threat and cameron Jordan at le with edge threat elite.

My first question is if I pinch my dline in this formation does that negate the edge threat abilities as they are not necessarily on the “edge” anymore?

Secondly what traits are best for rushers in this formation? Should I be using de’s instead of olb’s with power rushing traits? 

Any advice on this and how to effectively choose the best players based on their traits to fit schemes would be appreciated