Hoping the game will show you the answer, so just the basics:
1) Go to the outpost you want to steal.
2) Click on Hostile Actions.
What do you see?
Problem is likely that the Hostile Actions did not display an option to do this. Which in turn is likely related to some of Chris' defensive armadas still being present
. I assumed there to be a single mission that i can take to engage all of them *and* take the outpost
.
As a sidenote, how do i interact with outposts that are not Build on the Hydral homeworld remains? Could find no trace of them
...
EDIT:
Mantissed