I'm not sure what languages Original Sin will be released in. In a comment of the blog post The cost of dialogue in games
, Sergei Klimov wrote "Dragon Commander will most likely ship in French, German, Russian, Polish and Spanish (probably, Japanese, too) - in addition to English."
With their previous games Larian did the English and German releases, with publishers responsible for localization in other regions. Since they are self publishing the upcoming games, they may have kept ease of translation more in mind during development (though I don't know if that would effect the cost or probability of additional localizations).
Original Sin will ship with an editor, which could make fan-made translations easier (someone translated D2:ED into Hungarian, for example, and there was at least an attempt at Portuguese and Turkish).
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