We're constantly updating QBO to have this option added soon, dalanaseer.
Printing the invoices in Arabic is currently not an option in QuickBooks Online. At this time, there are only five supported languages in the system. These are:
I'd like to encourage you to let our software engineers know this is something important to you. I know that there are other users out there who also request to have this option added. You can send your feedback using this link: http://feedback.qbo.intuit.com.
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