The Homunculi names in Full Metal Alchemist 2003 (the question is aimed only for FMA03 and not FMAB as suggested from the title and contains uncovered spoilers for the anime)

I have a little trouble that the homunculi called after the 7 sins by FMA03 way, and I will explain.

In the FMA03 anime homunculi are created by failed human transmission, if that so, what makes them go by the title of the "7 sins" as Envy, Pride Lust an etc., it's hard to me because: if there were than more 7 people in the world trying human transmission what they would called? second what makes them to be after the 7 sins in their behaviour if they are "failed" and didn't deliberately created? my main issue is, why they needed to be called after the 7 sins anyway? what for?

I thought this through and this is what I got:


I could have said that Dante made them that way by make them eat the red stones and by that they got those emotions and behaviour, by Dante management, it could were the truth if not for the creation of Wrath that didn't made to be look like human by Dante and his behaviour was "Wrath" from it's origin and didn't grow up by intervention. (which is another question not for here, how it grew up to be human shape without red stones)
I could say that is only Dante way to call her fellow homunculi after the 7 sins, but in this way I will have to say that she couldn't except that Izumi's homunculi will be Wrath or any other sins to go after some pattern unless we will say the first answer.
I could say to answer for both of those answers that Dante knows that the spirits for the homunculi behind the gate can be only one of the 7 sins, but this one not only needs hard evidence but hard to say since there can be 2 or even 3 Pride or Lust.


Anyway I would glad to be enlighten or I missed a thing.
As far as I know, there is no certain canon answer but there are quite some hints.


At the end of FMA03 we see Dante doing something to Gluttony removing his intelligence and personality and replacing them with an endless hunger for energy. So Dante being directly responsible for the 7 sins symbolism is not out of the question but it does not quite add up.
Since every homunculus follows the theme of their name, we can rule out the possibility that it is just Dante calling them names.
This "spirits of homunculi"-idea is based on Wrath (Sensei's homunculus), right? He tells Ed about his time behind the gate and how he acquired Ed's limbs. But he never said anything about originating there. Unlike Manga or Brotherhood, there is no connection between Homunculi and the shadows behind the Gate. Sensei created Wrath after losing her child and after realizing her mistake, she put him on the other side of the (still open) Door. 2003 Humunculi are just sentient bodies that are very similar to humans but have neither soul nor a healthy personality.


I originally thought that the 2003 homunculi followed the sin that led to their creation but while Lust was created by her lover, Envy was created by Hohenheim back when he thought himself to be omnipotent. So it is safe to say that the homunculi are by nature always "born" into challenging circumstances and are unable to form meaningful relationships to process them. Dante might influence them to make them easier to control but even without her, they are unhealthy beings that are driven towards spoiled and extreme personalities.