Southern American? It's Argentine or Chilean?

You're thinking of "South America" (parse as "South America + n", or "from South America").

Given the context of "American English" and "Atlanta", I'm assuming they're referring to https://en.wikipedia.org/wiki/Southern_American_English

I agree, but I wasted like 5 minutes parsing the title.

(I imagine that it has the errors and bad pronunciation of a tipical Latam person, that is different for example from the errors and bad pronunciation of a tipical Spanish person)

Yea I tried to squeeze info into the title - could def be better. But no this is referencing the southern states in America.