So this seems like a waste.Many times I tried to sell outpost and the A.I would never offer much worth while.It just wasted my cash.Seems like busted trait imo.

It's super situational, but one of the good times to use it is if you want the empire bonus from a minor faction, but the system is located somewhere you'd rather not be either due to bordering an aggressive empire, or because the system generally sucks. For example, I'd happily pay bribes/do quests/pay influence for Thinkers and Tinkers (Pulsos I think), but I don't want a system of two ash worlds, one with a negative anomaly, bordering on Craver space. So I'll give it to an AI/sell it through system vacate. This is especially good for generating tension between two aggressive AIs, so they leave you alone. 

I don't play Lumeris that often, but I can also think of some weird cases where swapping systems might be good for generating the best trade routes. But yeh, it's a very situational trait.