I understand the issue you're having and will try my best to assist you in this matter.
To display the reviews on the default product on the translated version of the product as well, you need to activate the 'show reviews in all languages' option within the WooCommerce Multilingual plugin.
- Please go "WooCommerce >WooCommerce Multilingual > Settings" page
- Scroll to the Product Reviews section and enable the "By default, show reviews in all languages" option. Save the changes.
After that, the translated review will appear correctly in the Translated product.