I finally found the source of the leaked picture of fat-Technical Boy. It's from the Instagram account of Colin Penman, an expert at makeup and special effects that works on American Gods. He released a lot of sweet, cool and very interesting pictures, so I'll upload them here, not only for educational purpose, but also to see if some of these could be used in pages galleries.
Note: these are only the pictures for season 1.
Link to Colin Penman's account: https://www.instagram.com/colin_penman/
Emily Browning[]
There's a lot of pictures of Emily Browning. Some of her as an undead, armless zombie, but most are about her transformation into Essie MacGowan. Colin Penman is especially proud of her freckles.
https://americangods.fandom.com/wiki/File:BTS_1_Essie_freckles_.png https://americangods.fandom.com/wiki/File:BTS_1_Essie_freckles_Two.png https://americangods.fandom.com/wiki/File:BTS_1_Essie_test_1.png https://americangods.fandom.com/wiki/File:BTS_1_Essie_1.png https://americangods.fandom.com/wiki/File:BTS_1_Essie_2.png https://americangods.fandom.com/wiki/File:BTS_1_Laura_undead_and_Essie.png https://americangods.fandom.com/wiki/File:BTS_1_Laura_armless.png
Easter's party[]
Here are pictures related to Easter parties. Including the BTS picture of a tattoed Jesus, Kristin having her makeup done, and other stuff and Jesuses. https://americangods.fandom.com/wiki/File:BTS_1_Easter_Party_fun.png https://americangods.fandom.com/wiki/File:BTS_1_Easter_Party_Tattoo_Jesus.png https://americangods.fandom.com/wiki/File:BTS_1_Jesuses.png https://americangods.fandom.com/wiki/File:BTS_1_Ostara_Makeup.png
Lucy Ricardo[]
Here are a few shots at the filming of the scene where Media embodies Lucy Ricardo. https://americangods.fandom.com/wiki/File:BTS_1_Media_Lucy.png https://americangods.fandom.com/wiki/File:BTS_1_Media_Lucy_2.png https://americangods.fandom.com/wiki/File:BTS_1_Media_Lucy_3.png
The Old Gods[]
And now a bunch of BTS pictures about the Old Gods. We have shots of Mr. Nancy's hair, the Jinn being painted, Yetide showing off as "Disco-Bilquis" and the special effect for the wounded/dead version of himself that Mad Sweeney witness on the battlefield, in the episode "A Prayer for Mad Sweeney"
https://americangods.fandom.com/wiki/File:BTS_1_Bilquis_Disco.png
https://americangods.fandom.com/wiki/File:BTS_1_Bilquis_Disco_2.png
https://americangods.fandom.com/wiki/File:BTS_1_Jinn_getting_ready.png
https://americangods.fandom.com/wiki/File:BTS_1_Mr._Nancy_hair_1.png
https://americangods.fandom.com/wiki/File:BTS_1_Mr._Nancy_hair_2.png
https://americangods.fandom.com/wiki/File:BTS_1_Sweeney_his_own_death.png