"She wears" does not necessarily have to indicate a habitual aspect; it is quite a valid form of the simple present tense as well. Whereas the process of adding -ing in English actually represents the present continuous tense.
As such, I think "she wears" is quite the valid translation for mặc.
First of all, wikipedia isn't the best source for referencing. That aside. The 'simple' present is not all that simple. Simple present has a habitual aspect to it. Or perhaps, usual would be a better way of saying it. The sun rises in the east, he gets up early. This is the norm, the usual the current state of things. I play soccer, I brush my teeth, we eat dinner at 6. It is present, but it has an additional aspect of regularity imbedded in it.
https://learnenglish.britishcouncil.org/en/english-grammar/verbs/present-tense/present-simple Bullets 2 and 3 from this page express that as well.
Something that happens again and again in the present or something that is always true.
I may not have to be habitual. But in the case of the English sentence above, it would be understood as something she often does.
I know this does not translate between vietnamese and english. That is the challenge translators have. If i were translating Cô ấy mặc một cái váy or Cô ấy đang mặc một cái váy, i think I would translate both as "she is wearing a skirt." to get the right idea across.
https://learnenglish.britishcouncil.org/en/english-grammar/verbs/present-tense/present-continuous "something that is happening at the moment of speaking"
I never stated it only represents the simple present; my point was that the basic infinitive form of the verb also represents the simple present. As per your own link, bullet 2 has the addendum of "We use words like sometimes, often. always, and never (adverbs of frequency) with the present tense." Secondly, you ignored the first bullet point which merely states "something that is true in the present."
A basic form of the verb can have several meanings, depending on the context of the sentence. You have also ignored the fact that adding -ing makes the verb into a present continuous tense, which may not be the best form for the given sentence.
It is in my opinion "She wears a skirt" is perfectly valid.
Technically yes. What I'm trying to express is that in the situation this would likely be used, ie. pointing out the girl with the pink dress, if one were to say "she wears a pink dress" it would flag the speaker as a non-native english speaker. It is grammatically correct, but not natural.
When translating you ballance accuracy, naturalness, and clarity. this is accurate, and clear, but not natural. I don't expect the translation to be changed because it is easier for a learner of vietnamese in this format.
My initial question was just to see if the habitual aspect of the simple present that would be understood in English is also present in Vietnamese or not.
A simple, "No, vietnamese simple present does not have a habitual aspect to it" would be sufficient.
In this case, while we wouldn't use this phrasing much in English, its purpose here is to learn the Vietnamese. While it's true most Vietnamese use the simple present where English speakers use the present participle (ing), in translation, it's still "She wears a pink skirt." For reference, "Cô ấy đang mặc..." is "She's wearing...." if you really need it.