/Set-SetupUILang: Defines the default language that will be used by setup. If this language cannot be used, setup will fall ...

/Set-SetupUILang:

  Defines the default language that will be used by setup. If this language
  cannot be used, setup will fall back to English.
  This command is not supported against an online image.
  A distribution path is required.

    Example:
      DISM.exe /Image:C:\image /Distribution:c:\dist /Set-SetupUILang:en-US