[ WIP ]
Currently, most wiki sites were grouped under language codes, projects. [1]
However, there are cases like **wikimedia wikis with region codes as prefixes. [2]
We should figure out a strategy to handle the situation and group regional wikis.
[1] https://meta.wikimedia.org/wiki/Special:SiteMatrix
[2] https://meta.wikimedia.org/wiki/Special:SiteMatrix#mw-sitematrix-others