Are you sure? For Evangeline I've only ever heard Eva or Vangie (van-jee). But in Afrikaans, and therefore probably Dutch, Engela is used instead of Angela, and I could see Engie being a nickname form of that. It would be eng-ee, with no g or j sound. I've never heard it used, but it could be possible, except that eng in Afrikaans means narrow and especially narrowminded!