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You can download all existing translations to excel. Click "Download messaging translations".
You can then translate the messages into your desired language, but be aware that CommCareHQ doesn't support accents in these messages and they will have to be left out.
In addition, in order that your translations are uploaded, you will need to put them in a column labelled with your desired language (see example below).
If you now try to download the messaging translations, you will find your translated version along with the previous default language (likely in english)
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