I would like to create helmet wearable by cleric or fighter, but I guess maybe it is not possible.
Mm. That should be no issue? I've just tested creating a "Helm of the Brave" restricted to Fighters and Clerics, in the Windows version, it worked.
Please simply type: Cleric,Fighter in the Restrictions text box of the item (from the Item Editor).
If it still doesn't work, please let me know. Thank you!! Best regards