I’d consider hiring an assistant who speaks the language as another option. Otherwise- yeah you need at first a loose timecoded translation/transcript of all the footage you think you might use in your edit. Google away for places that handle this.
Then once you have a completed edit, you’ll do another more careful translation of the final edit for subtitles of which there are a number of third party plugins that can take timecoded subtitle transcripts and turn them into FCPX titles.
Noah
FCPWORKS – FCPX Workflow
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