How you express emotions is unique to your personality type. How you smile, laugh, or express anger depends on your unique temperament and values. I’ve found that if you know a persons personality type, you can also easily deduce their enneagram type based on their normal expressions they engage in and the emotions they express. I offer MBTI and Enneagram typings for anyone interested in gaining more information on their type and their enneagram type/s. 
Introversion and Extraversion
In my exchanges with introverts and extraverts I’ve literally noted that introverts tend to be happy or satisfied when extraverts are anxious or angry, where extraverts tend to be happy or most satisfied in situations that tend to bring up anxiety and anger in introverts. This often adds to some really interesting exchanges between the types but also show a truth about what happens when an introvert tries to be more extraverted. Not only have I found introverts to have more angry or frustrated eyes when their eyes are open wide, but extraverts tend to look the most upset when their eyes are squinting slightly. The two types show anger differently and become upset in different situations. When angry or dissatisfied, we tend to tap more on the 8, 9, or 1. 
Intuitives and sensors
The most amusing pattern related to intuition and sensing is that intuitives tend to have darker, more fluid, more watery eyes. When they feel the most energetic and interested, their eyes are more apparently reflective, like staring into a lake. Sensors have more dry and clear eyes, and their eyes are typically more bright too, like looking into a white wall. When sensors are forced to engage in intuition and when they lack a concrete outlet for their energy, they will appear more disinterested and bored, and their eyes will deflect more and look more dead. When intuitives are forced to engage in sensing, their eyes become more dry and bored, and their gaze becomes more empty. They can pay attention and use sensing, but will generally appear annoyed or forced in their gaze. When bored or drained, we can often tap on the 2, 3, and 4. 
Feelers and thinkers
What most separates feelers and thinkers is warmth and redness in the face. But also softness. Where feelers have more warm, soft faces, thinkers have more stern, rough, and cool heads, sometimes described as expressionless, but also more polished and clean. When thinkers become more warm or emotional they can typically be described as a little “uncomfortable” just as when feelers start tapping strongly on thinking, they may show discomfort, like an uncomfortable and forced toughness. You can easily tell that they don’t enjoy what they’re doing, but sometimes it’s necessary. Commonly, it’s the 5, 6 and 7 that will appear the most uncomfortable. 
Judgers and perceivers
Typically, judgers will consistently smile more with their upper lips, and perceivers with their outer jaws. This is where the smile will start and spread to the most. The judging smile appears more deliberate where the perceiving smile appears more unintentional (though neither of them necessarily is more or less deliberate)
Judgers have overall stronger expressions, but weaker reactions. Besides this, you mainly see judging in the mid part in the eyes, as it can stretch all the way up between the eyes, giving judgers a more focused gaze. Perceivers have more expressions in the part outside their eyes, giving them a more broad eyed, open minded gaze. What you will see is that when a judging type uses these muscles more, they also tend to appear more shameful or fearful, as if they’re trying to avoid something. In a perceiver, you will rather see courage and passion when these muscles are used. When a perceiver narrows their eyes and pushes up their upper lips, typically, that look appears more fearful, wavering, and ashamed. Typically, it’s the self-preservation instinct, the sexual instinct and the social instinct that appears the most fearful or shameful like this.
This is just the surface of the world that is reading emotions and personality and understanding the unique traits of each MBTI and Enneagram personality type.