I avoid Rheinland and Kusari because my bosses don't want me there. Anywhere else, I go because my ID does not forbid it. I have been to the Sigmas.
Generally all that happens is that people tell you to go home, back to Bretonia. Whenever I enter Liberty, even though liberty and Bretonia have treaties allow each others military and intelligence to go to each others houses, people will still accuse me of spying on Liberty, threaten to tell the Navy/Police/LSF/whatever and tell me to go back home to Bretonia, treating me either like a spy or a lolwut.
Which is really hilarious because I always ask the 5th or [LN]'s permission to enter Liberty before I enter Liberty. They've told me lots of times that I don't need to ask as well.
When I was in =LSF= back in 2009-2013, I encounter the same BS. People telling me to go back to Liberty. Actually, hilariously enough, some people back then even told me to leave Liberty because 'spies aren't suppose to operate at home' or some nonsense like that. Guess they've never heard of the FBI.
tldr: people tell you to go back home even though your ID does not restrict you from going anywhere.
Thanks for telling me about your experiences. The Sigmas have plenty of criminals for the LSF to engage with, though, and I think this time, things will be more interesting.
Also The Order is welcome to play the primary antagonist in this challenge, if they want to.