Claudio, your guesses for #3 are reasonable but not correct. #3 is an American artist named LeRoy Neiman. All the guesses centered around Impressionism and Pointillism, which image #3 definitely indicates. Unless you are familiar with Neiman's choice of colors, it would be difficult to get that one.
The other remaining image that hasn't been identified is #11. It is Alphonse Mucha, a Czech artist most identified with Art Nouveau.
There's nothing clever about the code. I just chose a representative image from an artist's work and used it to style the Che photo:
ImageRestyle[cheImg, .87 -> miroImg, PerformanceGoal -> "Quality"]
Each render took about 45 minutes, and sometimes I had to experiment with the weight (the .87 in the example) to get it right. With higher weights, Che is less recognizable. The default weight is .5, but the results seem to be more interesting with higher weights. For the project I'm working on right now, a revised version of the game Chicken Scratch, I rendered out 76 such images, some with the Che photo and some with a photo of Albert Einstein. I tried other base images including the Mona Lisa and Nelson Mandela, but Guevara and Einstein produced the most interesting results. I think it was the hair and eyes on both that caught the neural net's attention. My favorite is the Che/Hokusai in the 12-panel image at the top of this post.