Afaik, the anti-gang code comes into play when I'm fighting three or more opponents. Will Ehren soul help when I'm fighting just two? How about Master of Ukemi, will it give acrobatic evades with just two opponents aiming at you?

I didnt truly notice a huge difference until people were trying to gank the living hell out of me. Which happened a lot. So as playing Elleryne it was invaluable to the situations I would get into. That being said. I wouldnt say the difference is huge between fighting one opponent and fighting two. But it shines in situations where you normally would get clobered by 3 opponents. They miss bashes or trips or other important things that make you live. Sometimes. :)

Elleryne had both Master of Ukemi and Ehren soul.

Depending on situations you get into, it might not be as valuable to you as one of the other edges.