Well, it's not fully functional, but yes, a Minecraft Pro figured out how to create a nearly functional Pokemon Red simulator. The YouTube and Reddit user goes by Reqaug, and this video is popping up everywhere…
Take a look for yourself:
https://www.youtube.com/watch?v=o5DwPgYp6vkVideo can't be loaded because JavaScript is disabled: Working Pokemon GBA in Minecraft (1.10 – Structure block[...]