wikia is not nearly as popular as gamepedia, also i already started the wiki and many contributors are joining, i will work on the gamepedia wiki no matter what, and i want the official sprites so i can upload them to the gamepedia wiki.
Fair enough, I dont think anyone has any sprites. You will probably have to settle with some screenshots at first. So far the dev haven't come out with anything in that direction. It will probably be more relevant once the game is actually out :)