Ok…did a little look at some stuff and this is what I think:
The icons for Sombra, DM, and Baptiste seem legit, but not the bottom left one.
While it could be an icon for a new costume, it still seems…off.
Some mentioned Hammond, but his ears are bigger than the ones in the icon.
Some say Moira, but if you look at her Face Icon spray and compare it too the icon here, she doesn’t have anything on the side of her face besides that metal thing over her left eye.
The only time she does is in her archives costume…but her hair is like it always is and not fuzzy(and if she has the hat on…it doesn’t match the shape of the top of the head). Her hair line also is off too unless she has on a helmet.
Widowmaker…is a 50/50 honestly. It could only be a new skin because nothing else she has really matches up with it. However, she’s the only one with the highest chance it could be since her recon visor would fit the “hairline”
My only guess is what she has on during the event is a prototype of the recon visor that she has now. It could even be possible that her hair is just messed up after the brainwashing.
The only thing that even remotely matches that fuzzy head with small ears…is Zarya’s 2018 Winterland costume, but even that isn’t a 100% percent match(plus it would be weird lore wise for her to be there).
If all else fails…then this thing is a fake.