Prerequisites
The DataManager is open with a manufacturer selected (Home tab → Edit Database Settings)
Steps: Export
Click Export (Options tab → Translation group). The Export translations dialog opens (this runs through the Poolmanager, the same pattern as exporting a manufacturer module or component tables).
Select the message set from the Messages to be translated dropdown (e.g. "1: Common components" — the dialog shows how many messages that set contains, e.g. 186).
Choose a starting language, if you want one, from Translations from — this pre-fills the export with an existing language's text as reference. Or click Add a new language to start from scratch.
Add another message set to the same export, if needed, via the add another translation module (+) control.
Click Target Filename and choose where to save the Excel file.
Click Export to Excel file... to run the export.
Click Open in Excel, if you want to review or start translating immediately.
Steps: Import
Reviewer note: the Import side of the Translation group hasn't been seen in a screenshot yet. Presumed symmetric to Export (pick the completed Excel file, select the message set and language, import) — not confirmed. Flag if you can share a screenshot of it.
Result
A language's translated text is added to the relevant message table(s), available wherever those messages are displayed.