You can manage your Microsoft Advertising Editor account in one language and run ads in a different language.
Your Microsoft Advertising Editor product language is based on your operating system's language and region settings. Available product languages include English, French, German, Italian, Brazilian Portuguese, Spanish, and Traditional Chinese.
Your ad language setting determines the language you will use when you write your ads and should be the language of your customers.
Your ad language in combination with your location targeting determines who will see your ads. To learn more, see How does location targeting and ad language affect who can see my ads?