Here is a list of all the leaked v11.20 Fortnite cosmetics that have not been released in the game as yet. The cosmetics include Skins, Back Blings, Pickaxes, an Emote & Wraps.
Epic Games are always adding new cosmetics to the Fortnite Item Shop for players to purchase and cosmetics that are available to purchase include Skins, Pickaxes, Gliders, Emotes & Wraps.
When new updates are releases for Fortnite, data-miners are able to access the files and leak anything new that has been added, as long as they have not been encrypted. The most popular files to leak are the cosmetics and in the v11.20 update, there were many cosmetics that were found.