Well, my current game just got weird. I am playing as a xenophobe, authoritarian spiritualist oligarchy that has the slaver guilds and syncretic evolution civics. So you can guess where this is going. I spawn near about eight primitives. Unfortunately, infiltration now requires the basic biomodding tech, so I just skipped colonizing and started invading until I got to my core cap. Due to various reasons (habitability, mainly) I had to set all but the syncretic evolution species to caste system (my main species gets full citizenship). End quick overview of the Holy Nautil Empire.
Right next to me spawns the Lyrite Galactic Technocracy, xenophobe fanatic materialists. So you can guess tensions happened (they actually attacked me and lost). Outwards through the spiral arm is the Havoll Interplanetary Republic, who are egalitarian fanatic materalists, so they hate me. They've also buddied up with the Lyrites and forged a defensive pact. In the next arm, I meet two powers. One is a xenophile fallen empire that really likes me for some reason. The other? Xenophobe fanatic spiritualists, the K'Taknor Holy Nation. They immediately NAP me. Soon after, they offer a defensive pact, which I accept. But that's not weird. What is weird is that they just offered me a federation offer. The first federation at all in this game, in fact. Just them and me.
So far there are exactly two non-FE xenophiles and a single pacifist (not a xenophile either).