^Or it might not be an empire at all. I don't see any reason to assume it still uses the name after 2161, unless you can cite some text in which it actually does.
All we know with any certainty is that the Andorian Imperial Guard is still called such in 2376 in Andor: Paradigm
. I'm inclined to interpret that as indicating that their state is still called the Andorian Empire, but your mileage may vary.