The Overseer Outposts are commonly referred to as such throughout the game. Furthermore, Karnaca Enclave would suggest there is only this one Overseer base in Karnaca, which is not true as there are outposts found in at least three missions, in different areas. Please keep the outposts as such.
The reason I changed it last time was that the in-game map was called as such, implying it's the Karnacan equivalent of the Office of the High Overseer. That time, I simply removed the letter 's' from the end of the word Overseer, as that is grammatically incorrect. It is now called, as you said, Overseer Outpost.