I've had an ENFP friend for about 18 years (I think [dates aren't my strong suit, ask my nephews ]). The whole introverted extrovert is on the one hand IME total BS and on the other very true.
90% of you know I'm on about Dom so I'll quite trying to conceal.
With Dom he can be extremely introverted and even quite T-ish. Gen got a shock when she witnessed just how close to INTP thought trains Dom can get. However he is gregarious when partying and can be a total pain by just making soo much out of everything. He can do the "won't shut up even if struck with baseball bat" side and also the "been here ten minutes and all I've got is a flicker of the eye ball!!".
Makes me think that ENFPs are not talked about so much cause we'd actually have to wait for them to decide who they are before we could describe them properly