This plugin is 100% compatible with WPML.
This means you will be able to get different badges on the same product, according to the language the users are using.
In order to create a different copy of the badge for one of the languages configured using WPML, access the badge edit page, select the language and click on the “create” button.

translate badge

If this operation worked as intended, you will be automatically redirected to the edit badge page for the language you selected.
From here, you will be able to configure the badge starting from scratch as you usually would.
The next step will involve applying the badge to the translated copy of the product.