If you want to talk about swarm intelligence, something we actually see in nature, we can talk about that. But that is a distinct thing from a hive mind- hive minds are a fictional concept. Xenomorphs don't really display a hive mind. They're also irrelevant for trying to model an empire in Stellaris off of- because they're animals with no spacefaring capacity.I would argue that you have a very rigid definition of a term "hive mind".
https://en.wikipedia.org/wiki/Group_mind_(science_fiction)