Its not a glitch. its how the gear was made so you cant get int 2times with 2 diff LA or HA armor parts.
I'll just drop the bomb now
Get a Heavy Dragon helm, lvl your str until you can wear it. equip it
Now get LVL 110 Heavy boots. Due to the str of the dragon helm you won't need to put too much str and due to lvl 110 boots it will be less str to put too
You will get the int bonus even if its not displayed.
But I don't recommend that in PvP. Mobbing is good but not PvP. Go full LA for PvP