After extensive research, I’m not totally sure on whom the original artist might be but they are prevalent. One of them, in fact, you've noticed on some of this websites advertisements- hosted by mgid.com. Also posted below is a Batman gender-bender which, from the looks of it, may be from the same artist.
Alison Brie-Captain America
Amber Heard-Thor
Sandra Bullock-Iron Man
Anne Hathaway-Batman
Being a huge of fan of “what if” material, I find this work to be rather provocative. I only hope that the original artist would continue to give us more of these type of images. Well, what do you guys think?