That string is located in /word/vbaProject.bin/Zotero.bas inside the Zotero.dotm archive.
As you've seen, it's certainly possible to localize the Zotero Word template file. The difficult part is efficiently switching between localized strings within the Word add-in based on the system locale.
More than that actually -- it's also difficult to effectively create those localizations in a way that they can be built easily from files translated by users. The framework Zotero is built on provides an easy way to do that with language strings being stored outside the actual code. That is not available as an option for Word.
@adamsmith thank you for your reply. Then how could i localize /word/vbaProject.bin/Zotero.bas? It seems only this string is not localized in my Word Mac plugin.
You should open Zotero.dotm with Word, go to Developer tab (enable it in Options), open the Visual Basic editor and change the string there, then save the template file.
You might need to move the file out of your startup directory before editing and move it back in afterwards.
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I have localized the Word plugin almost 90%. Please see:
http://i2.bvimg.com/619250/de57e75fe0ab00af.png
But yet this string cannot be found. Maybe this is in Word not in Zotero Plugin.
As you've seen, it's certainly possible to localize the Zotero Word template file. The difficult part is efficiently switching between localized strings within the Word add-in based on the system locale.
See that it is just a text file:
https://github.com/zotero/zotero-word-for-mac-integration/blob/master/build/template/Zotero.dotm/word/vbaProject.bin/Zotero.bas
You might need to move the file out of your startup directory before editing and move it back in afterwards.
http://i4.bvimg.com/619250/606ebb5071f20f2c.png