Although there is no guaranteed way to unlock them, you can get this article if you level up which will earn you rewards, and you can be awarded the wings, for this you just have to play and level up.
If another member of the crew unlocks a cosmetic or item, it will apply to all those who make up the crew as long as they are in the same timeline, but if the one who unlocked the wings is not in play, no one else will be able to unlock them.
Those who participated in the Knockout City Cross-Play Beta in April and managed to unlock the wings will be able to equip them through the "Customize Brawler" menu as long as they use the same EA account.
I hope this article helps you know how to get wings in Knockout City, and you can enjoy them with your crew.
Microsoft Windows PC, Nintendo Switch, PlayStation 4 PS4, PlayStation 5 PS5, Xbox One , Xbox Series X/S