Some interesting SPOILERS in that clip note!
Guess I'll make sure to get the Nightsong in Act 1 huh.
But yeah I agree the pictured figure is almost certainly NOT an Aasimar (they don't have big feathery wings for bloody starters mate! "Spectral" at best!), but yes someone is if the voice lines are right.
Doesn't mean it'll be a PC race, but honestly, if they're going to go to the trouble of coding them in rules-wise, you can just make them be a human with different coloured skin/hair, so why not?
Also was that a male narrator? That's weird.
Probably the same choices? Not sure why they wouldn't be. Non-binary is not the same as intersex - some intersex people are non-binary but most identify as one gender or the other.
Aasimar can have big fluffy wings, with the right feat in 3.5e your Aasimar got big fluffy wings, and AL allows you to choose an Aasimar version of the the Winged Tiefling, trading your subrace features for big fluffy wings.
Plus the Fallen Aasimar's black feathered skeletal wings aren't "spectral" either, which means either they aren't finished with the SFX on Aasimar wings or they want more physical wings for BG3 Aasimar to make them more visually distinct from humans, like tails and horns are for Tieflings.
I mean it's not like Larian has never taken any artistic license before.
And ita not like "spectral wings" are a deep long running piece of Aasimar lore. The DMG Aasimar has no wings, neither do Scourge Aasimar, 3.5e Aasimar didn't have wings, unless you took a specific feat in which case they got big wings, 2e Aasimar had no wings. Serious the spectral wings thing isn't as important as folks think it is.
I don't think the wings will do anything unless you use a racial power with them, just like you can't gore someone with Tiefling horns or trip enemies with a Tiefling's tail, its an aestic flavour thing.
And given that earlier versions of EA has racial tags for Aasimar, no way in the nine Hells do Aasimar not end up playable in full release.
The male voice is a villian of somekind, although their has been a datamined male narrator as well as origin character narration.