There is: uBlacklist[1]. I've been searching for the exact same thing to get rid of Indian tutorial scamsites, bad GitHub and StackOverflow clones and, of course, Pinterest results :) Can recommend.
[1] https://chrome.google.com/webstore/detail/ublacklist/pncfbmi...
You can try this extension. It was forked from a project once maintained and abandoned by Google themselves.
https://chrome.google.com/webstore/detail/personal-blocklist...
https://addons.mozilla.org/en-US/firefox/addon/personal-bloc...
Maybe a place I can upload a HOSTS file?
Or an extension that adds this to every search?