I've seen this type of system implemented on PartyServer, and I'm pretty sure with the way Plan B's account system (MySQL Database) works, this can be added.
A user would be able to set a language for their account (via In-Game or Control Panel), and they would be able to see everything in that language.
It would benefit this community, because there are many players that are unable to speak English at a perfect level, which gives them a disadvantage in understand the meaning of commands ingame and rules especially.
As for taking care of the translations, I propose a community effort in helping out with that.
Starting with the languages that are the biggest priority on this server.
Spanish, Hindi, Arabic, and French.
People who are super fluent in these languages would work with other fluent speakers, or by themselves and publish translations of commands, that we would write out in English on a topic to be translated.
People who helped translate, can be rewarded in some way that we would figure out.
Optional, we can add something that detects the country of a player who joins and sets that as their default language (if they aren't registered)