If you have problems with your Mouse/Mice using Example a modifier Shift on keyboard + 1 on Mouse.
Download( it’s free): Karabiner-Elements.
Follow instructions.
Go into Karabiner settings, go to Devices.
Look to right and look for your Mouse/Mice Name.
Click on your Mice/Mouse setting : Modify events
Log in to World of Warcraft and cheek.
If it works, you’re welcome 