Oh yeah, I caught a Shiny Munchlax and a Shiny Alolan Grimer in Pokemon Moon a little while ago. The Munchlax was while I was SOS chaining to try and catch a wild Snorlax (just so I could say that I did) so it was a much higher chance of getting a shiny, but the Grimer caught me completely off guard. Shiny Alolan Grimer has the same coloring as a regular Grimer, just with the yellow stripes around its mouth, and I was about to run from it since I was searching for a Trubbish (again, to SOS chain for a Garbodor) before I realized it was a freaking shiny.
Yeah, and i managed to get a shiny Cutiefly while trying to get a honey-gathering money printing machine. Although my first legit shiny was a magicarp from Sapphire.