Android & iOS
The language of your Wallet app is automatically set to match the default language of your phone. If you want to change the language of your Wallet app, you will need to change the language setting on your phone. However, if Wallet is currently set to English and your phone's default language is different, it means that the app does not currently support your preferred language.
Web App
Your Profile (located in the top-right corner)
Settings
Web App Language
Select your preferred language
Note: If your preferred language is not listed, it is currently not supported.