This wiki makes use of the Translation Plugin, which provides easy access to translations for wiki pages where they are available.
Wherever you see the sidebar pictured here you can click on any of the blue boxes to reach a translation for the current page in that language. A gray box signals no translation available.
Translations are done in a maybe per page basis as I feel like it.
For the most part, if a translation of a page is not available an online service such as Google Translate should suffice, as barring Pokémon-specific terms most content is English or Spanish neutral.