Nice compilation.
Still not sure if that girl was Stella. She looks different, but also resemble Stella. Huh.
I'm not 100% sure but as far as we know she is Stella, the trailer didn't say she was Luna, but the fact she heavily resembles Stella makes it the likely conclusion that it is her, even if they didn't say it was Stella either, and in the trailer dialogue itself the bit where they mentioned Luna and the bit where Prompto talks about Noctis's date are actually two different conversations, the way it was edited made it sound like it was a single conversation, and then cutting to a clip of her right after a specific name was mentioned further added fuel to it.
The way it is now there are multiple possibilities.
Either she is Stella's redesign and we are just now seeing it properly, seeing as they even changed Prompto from last year this isn't hard to believe, and Luna is simply someone else, either the black haired woman Hime-cut woman or an unseen character.
Either she is another character who looks like Stella, where if that is the case it would in any likelihood be Stella's sister, and possibly the "Luna" girl that was mentioned.
This "Luna" name could be a pseudonym that Stella uses.
Stella could have been simply renamed to Luna.
Luna is the black haired Hime-cut woman, and the blonde girl is Stella's unnamed sister.
Luna is an unseen character altogether.
And I'm sure many other various possibilities exist too.