hi CAROLINA,
Do you want to change the language of admin dashboard or front end ? If you wan’t to change the language of front end or interface Pro theme options then you need to create a .po and .mo file for the language translate.
If you want to change the default wordpress widgets, then there may be some plugins, recently we don’t know which plugins works for the dashboard.
Just try this plugins
https://wordpress.org/plugins/wordpress-language/ or you may even try the wpml plugins too.
Thank you!
.
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