Does it crash while working with a specific font? If so, try reinstalling that font or try contacting the font manufacturer. If that's not the case, is there anything specific that triggers the crash? Also, please share the crash report.
I'm not an After Effects user, however, just to assist with your issue, I just typed in Arabic, changed the font to different typeface, I didn't encounter the issue. Please provide more details so we may replicate the problem at our end.
My settings: Mac OS Big Sur v.11.6 • After Effects v. 18.4.1