cli-er supports internationalization (since v0.11.0) by acepting CliOptions.messages with overriden messages:
This way, you can redefine all messages used internally. The default (en) are declared in these two files:
In the example from this folder, the current language used by the user is stored in a configuration file (.intlclirc.json). This is then used to load the correct messages from the intl folder.