Is there any way to hotkey Active abilities on items?
Solution 1:
Each item slot, 1-6, is initially bound to the corresponding number key.
You can rebind this during gameplay if you wish, but I like to simply move activated items into the 2nd slot and hit 2.
Solution 2:
It has always been possible to cast item y using the number of item slot. Furthermore the patch note V1.0.0.125 added :
You can now Smart Cast items (you have to manually bind the hotkeys).