Things we know:
Girl 1 knows japanese and english, so does Stoic
Girl 2 can read and write, so can Friendly
Girl 3 is basically a blank slate, but does remember there's a secret on the island; thinks Shan is a human but thinks you should find girl 4, also knows what medicine is and does
Confident remembers Shan and Beauty are two different people, Shan was a man and Beauty was his first creation, Confident also knows Shan is flawed as in made flawed because she was the first try
Positive has zero short term memory but can remember when both islands were populated and what tools are and what to do with them even if you don't show her, so does girl 1, she can't fix a fishing pole but she knows fish are good to eat (but doesn't understand cooking until you show her)
Friendly remembers pregnant women and is sad she can't be a "real mom" and pretty much wants to adopt you
Confident remembers a mistake she made and wishes she was good at everything but accepts she isn't, she also remembers the island being destroyed and being hit by storms
Positive remembers spicy food being "scary"
Confident remembers that even if you don't like doing a thing it helps other people especially if they are in danger and trouble, and that everyone should "stick together" even if they don't get along or something bad will happen like before
Stoic remembers friendly animals and not undertanding why they were friendly
For an Illusion game there's quite a bit of meat this time around, thematically speaking.