[jrdres]

Believe it or not, there once was an 8-bit computer with native Arabic. It was a version of the Z-80 MSX series by Al Alamiah called Sakhr. It seems it could switch between English, Arabic, or mixed. (In fact, this was mentioned in the OP.)

I'm curious how it handled mixed entry.

https://forum.vcfed.org/index.php?threads/bought-a-al-alamia...

https://www.msx.org/wiki/Sakhr_AX-230