It’s funny that you use that word 
https://blue.mmo-champion.com/topic/38904-multiboxing-rules-and-semantics/
Semantics issue #1:
Is using one keyboard to send signals to multiple instances of WoW automation? In other words, what is the definition of automation as it applies to WoW?
Using a keyboard setup like what you’re describing? Not automation.
Setting up a macro with said keyboard that would, for example, automatically press Fireball each time it was available? Automation.
Semantics issue #2:
Software (such as Keyclone, Octopus, etc) to emulate a keyboard multiboxing solution is, by nature, “3rd party”. Is “3rd party software” synonymous with “bot” or “automation”? Are all types of “3rd party software” bannable?
Likewise, hardware, by nature, is “3rd party”. What kinds (or uses) of 3rd party hardware are bannable?
Is it sending an identical signal to all client windows or switching between them to send commands? Not automation.
Is it playing the game for you, or rather, for one of your client windows? Automation.
All hardware is considered neutral as long as its commands and features are not being used to automate gameplay.
I think the most relevant response to your current topic
Add in a 3rd party program. You press ONE button and all 5 screens react. How exactly is that fair/legit? It’s not. The ability to control 5 computers at once with 1 single keyboard and 1 single press of a button is automation. The ability to make your characters cast their individual spells and skills at once by pressing 1 button is automation.
Is not automation by our standards. This is why multi-boxing is just fine.
So to Blizzards standard of automation it’s fine. Automation is tricky, it’s not bad in itself, another example would be those addons that autovendor for you or autorepair.
More recently Auction House Much Slower Today - June 16 - #13 by Kaivax Blizz took action against users
using addon-driven automation to gain a competitive economic advantage over other players
So maybe one day Blizz will change their stance on Multiboxing but as of right now, by their standard, it’s not the bad automation.