Shop Uploader only supports English.
There are a number of translations you can add to your template.
These translations are for:
Dutch (Nederlands)
French (Français)
German (Deutsch)
Italian (Italiano)
Japanese (日本語)
Polish (Polski)
Portuguese (Português)
Russian (Русский)
Spanish (Español)
Note: You can only have translations for the title, description, and tags. These translation columns are at the end of the template. The first ones need to still be in English.
For more information on languages and translations visit the How do I add translations to my templates? article.
For more information on languages visit Etsy Languages.