Hello @franji,
Arabic isn’t supported by default, although you can use an Arabic font so that the characters are shown, RTL (right-to-left) requires a different library (our default is dompdf).
We have an extension that uses a different PDF library (mpdf) that does support Arabic & RTL & you can download the plugin zip in the releases section: https://github.com/wpovernight/woocommerce-pdf-ips-mpdf/releases
After activating the plugin, you can switch to the “Simple RTL” template which already has the correct font & text direction setup. ??