If so, this is further indication you're not ENFx. I'd say ENFJ/ENFP type 5 are extremely rare if not nonexistent.
Yes, the great majority of 5W4 are introverts. Most of them are primary or secondary thinking types as well - INFx is consistent with this Enneagram type, but isn't so common as thinkers.
I'm just going to ramble a bit around 5W4 INFJ - it might help you by finding parallels, or on the contrary by finding what is definitely not you. Sorry if I'm repeating anything, but it's best put all together.
From my own experience, one of the problems that INFJs face in confirming their type is that Ni is quite obscure and difficult to comprehend, even if it's your primary. The way it's described isn't necessarily going to be the way a particular individual experiences it, and our encounter with it in others is contaminated by the judging functions they have to use to express it externally. The important thing to understand is that it's a perceptive function - it sees but doesn't evaluate except like our eyes which distinguish form and differentiate one thing from another. It isn't anything like as defined and transparent as sight though - it's more like seeing a landscape from a hill in semi-darkness, with the sun coming in and out from behind clouds and spotlighting different parts of it, sometimes unexpectedly. It certainly isn't a 'nice' function, like Fe tends to be - it isn't nasty either, it's purely neutral, like sight.
As 5W4, you could be an INFJ that has well developed Ni but who has to put quite a lot of effort into using Fe - at the same time being actutely aware of others and their atmosphere from the way that Fe and Ni hair-trigger your apprehension of them very sensitively. That sensitivity doesn't come from Fe but from Ni importing others inside you through Fe and modeling them acutely, so you are very aware of them, feel them intensely. In some situations it can be painful, like a loud noise is painful to someone with sensitive hearing.
5W4 means that if you are INFJ you will spend a lot of time chewing over your insights, thinking them round and round in circles - sometimes this is enjoyable and rewarding, but sometimes, like at 4am some mornings, it's involuntary and can't be switched off and drives you mad. When you get this thinking and intuition linked well to its expression outside youself, you can come up with deep thoughts that may amaze others.
The flip side is that all that think looping may come with a lot of unfocused anxiety.
Inferior Se doesn't mean that we are incapable of crossing the road without getting run over. It does mean that a lot of complex sensation can overwhelm us, while energising other types. If I go to a book or antique fair, particularly if they are in a noisy, busy hall, I just switch off after half an hour - I just can't concentrate any more and find I'm looking at stuff and not seeing it. I'm the same in a noisy bar, or party - after a while I just can't understand what's going on any more and all my input tubes are blocked. This isn't a social problem (though I do find that side stressful too) but purely one of being overcome by all the various stimuli in the environment. Like I said a couple of posts ago, I'm quite capable of finding a load of grazes on my shins with no idea how they got there - it's a pain in the bum because thay take ages to heal up properly and it sometimes looks like I've got leprosy down there lol. Oh yes and my duvet cover keeps trying to bite me when I change the bed, but maybe that's demons rather than inferior Se.
I seem to flip between two different orientations.
On the one hand I can be very analytical, logical and wordy, particularly in writing - and very critical of what I say, so that I may go over it and rework it several times before I'm happy it caught my intention. I'm rarely happy that this process does actually capture my insight but it can be an OK approximation. I can easily overwork something in this mode and lose people in the complications - for me the insight that generated all these words is just a single easy to grasp non-verbal object, but it can't be expressed to others easily in language.
On the other hand I will use an image or a poem or a piece of music, etc, to communicate something, and this gets much closer to what I want to say because these can provide a rich simple symbol that expresses a lot of things in a single expression, just like the insight. When I make a picture or a poem of my own, very often the insight and the image are created together, so these are much closer to my raw inner vision than the wordy explanations can ever be.
I'll leave it there - it's just some ideas for you to play around with.
But a man without a shadow...
