The Mr. Meeseeks skin is an Epic Fortnite outfit. Mr. Meeseeks was available via the Item Shop for 1500 V-Bucks and you can buy it from Fortnite Item Shop when it will listed.
Fortnite Mr. Meeseeks Skin Details
Fortnite Mr. Meeseeks Skin PNG Images
Here is the PNG images of Mr. Meeseeks below!