I have not tried using different icons for different languages, but I have tried different display names for the same application in different languages. So, I'm not sure about this solution, but you can try. Here is what I did:
For French:
"CFBundleDisplayName" = "france";
"CFBundleName" = "france";
Here you can try to use the "icon files" property. Well, I'm still not sure. Hope this works.
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