So this big teaser for the teaser ended up teasing with a trailer that contained nothing except a few cutscene clips from older games. Gaming hype culture is so disgusting
To be fair, with tri-Ace being bought, and SO4 being announced as the end of the series, I think this is one instance where a reveal was needed. It's not so much about the game at this point, as opposed to who's making it.
I assume this was a deal put in place for tri-Ace working on XIII-2's combat, and essentially all of XIII-3 (which really shows, it's basically real-time Valkyrie Profile).
As to the other statements. There's a whole slew of Fellpollians. There's a Lesser Fellpool which is what Leon, and Merecle are. They have cat ears, whereas most people from Fellpool look like Roddix. They only have a tail.
It's further separated based on cat species. Cyus, and the king in SO4 are derived from tigers, which give a different appearance, larger builds, etc.
To be fair, Merecle wasn't the first cat-girl (that happened in SO1), she wasn't the first to turn into a cat (also 1), and she's not even the youngest Fellpool in the party (Leon's 12). She's basically there to be a callback to original's cat-girl. That said, she is annoying, and used poorly, and they should have done more with her character than what they did.