By default, the language displayed in Pokémon GO is determined by your device's language settings.
There are two ways to change the language displayed in Pokémon GO:
1. Update your device settings
The steps to change your device language will vary depending on the type of device you’re using. If your operating system isn’t listed below, please visit your device’s help center for more information.
2. Update your Pokémon GO settings
To change the language settings for Pokémon GO without changing the settings for your entire device, follow these steps:
In the Language section, you will see your current language settings. Tap the dropdown to choose from any of the languages that Pokémon GO currently supports.
Tap OK to accept this change.
Review the details of the language change and tap Save Changes to restart Pokémon GO with the new language settings.