When you create a multilingual template all language versions are automatically synchronized, but you are still able to set different themes to them. So what you need to do is register both your Arabic theme and the theme used by all other languages, and then set them to their corresponding templates/pages.
the Telerik team
Do you want to have your say in the Sitefinity development roadmap? Do you want to know when a feature you requested is added or when a bug fixed? Explore the Telerik Public Issue Tracking
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