Here is a list of all leaked cosmetics from the v11.10 Fortnite update that have not been released in the Item Shop yet.
There are quite a few cosmetics that were leaked in the v11.10 Fortnite update that have not been released in-game yet. These cosmetics include Skins, Back Blings, Pickaxes and Wraps.
It is surprising that one of the leaked Skins, Deadeye, has not been released yet as it looks like a halloween Skin that should have been released during the Fortnitemares event. All cosmetics could be released at any time though, but there have been instances where some leaked Skins have been adjusted before being released officially.