There is no built-in way to do it. You would have to write a custom script that unvotes all downvotes by going through each user's downvotes.
Should Norwegian Docs be removed from Github?
Through a web search I ended up on some very outdated plugin hook docs on Github that appear to be marked as Norwegian, but are in English. It looks like they haven't been touched since 2014 and contain mention of hooks that no longer exist (filter:post.parse for example).
github root for norwegian docs: https://github.com/NodeBB/nodebb-norwegian
@jongarrison Unfortunately a fact of life with some translations
If all of the pages are still in English, then yeah we may as well remove it. On the other hand, would you be willing to translate them?
Bringing them up to date with the latest docs in English is easy...
I haven't the slightest idea about Norwegian I just accidentally happened onto one of the outdated Norwegian doc pages while trying to find a hook name (which turned out to be wrong and obsolete).
@baris Thanks! I did eventually find the right link.