I would say difference in energy levels socially.
I know MBTI is not about skill, but generally I would say the ENFJ is probably more at ease communicating with people in general, and especially people they don't know. They can skim through a group of people and figure out just what needs to be said to this one or that. They are at ease in the group. I don't know if this relates to other INFJs, but my Fe is based on individual empathy, so I can do quite well one-on-one perceiving specifics about a person and communicating, but I cannot navigate a group.
ENFJs might also not be quite as off-beat from the norm as an INFJ will tend to be.