I just got back from seeing the movie. I enjoyed it, but wouldn’t put it among the very best of the MCU. I’ll start by quoting some of the posts from the Eternals trailer thread, and giving the answers based on what I saw. I’m also adding my own questions about the second post credit scene at the end.
It seems like the Eternals are in a sense “created beings” rather than fully living. My guess is that none of them got dusted because Thanos probably didn’t include them as living creatures when he did his snap.
The character in question is named Eros, and the information is provided by sidekick named Pip, who appears to be a D&D style dwarf or some similar creature. I assume he was being facetious when he introduced Eros, who appears to be an Eternal that was stationed on another planet, and not a member of Thanos’s race.
Speaking of post credit scenes, the second scene featured Circe’s boyfriend, Dane, who had mentioned a complicated family history. He is shown opening a large box with a sword. One would assume, given that he is English, that the sword in question is Excalibur. The problem is that Thena was already in possession of Excalibur during the movie, so this must be some other sword. The way it’s presented makes it seem like someone who has read the comics would know what sword it is, and who he is supposed to be, but I have no idea. The voice at the end asking Dane if he was ready sounded like Samuel L. Jackson, presumably getting ready to invite him to join the Avengers, but I’m not entirely sure if that’s correct.