Where to Find and Catch Shuppet
From Pokemon Go Wiki
Shuppet are found and captured in Nest and Habitat locations.
Nests
Shuppet Nests are locations that consistently spawn Shuppet.
Habitats
Shuppet Habitats are spawn locations where Shuppet is likely to be encountered, but not guaranteed the way a Nest is.
Additional Tips and Information
Best Nests
If you know a really good nest or any of the nests above is really good, list them here: