[OrthodoxPresbyterian]

It means they're born with a tendency to sin early....we know also via the New Testament that they have a sin nature.

No, the Verse doesn't say that at all. The Verse doesn't even hint at some vague, amorphous "tendency to sin", you just interpolated that in there because you WANT it to be there, even though it ISN'T there.

Psalm 58:3 is a Verse about Infants, and Sin. So let's just submit the matter to an acid test of spiritual honesty:

• A.) Psalm 58:3 teaches that Infants ARE SINNERS.
  
• B.) Psalm 58:3 teaches that Infants ARE NOT SINNERS.

It's either one, or the other. To claim that it is merely teaching a "tendency to sin", is to claim that the Verse is teaching "B".

So, which is it, Xzins: A, or B?

[xzins]

I have already said that they have a sin nature, OP.

I have also said that they don't speak/verbalize....that that is as metaphorical as the verse that says they have fangs like lions.

So, they are sinners by virtue of their sin nature. BUT...they don't "speak."

Both can be true in this instance due to the obvious metaphor.