In Keybindings, you can set something to save camera view.
There are four or five different camera views.
Basically pick one, doesn't matter which, and assign a hotkey to it.
Pick the same view number on each toon.

Now select your AoE view of choice.
Try to get the same angle and zoom distance on each account.
When they're as close as possible, press your hotkey to save the view.
Repeat for each account.

You can go back into keybindings and unbind the key to save that specific view.
You might need to log out, for it to write your settings to the config file.
If you crash or Alt F4 or red X to exit the game, you won't have settings saved.

Next you want to pick a Keyclone hotkey for AoE clicks.
I believe the option is called, send next click, or something very similar.

In WoW, you want to put a macro on this same keybind.
So when you press the key, it activates the wow macro and also the keyclone send next click.
Your wow macro will be similar to this:

#show Hurricane
/Script SetView(4);SetView(4)
/Cast Hurricane

Change Hurricane to the ground target spell of choice.
Change the (4) in SetView to the View you have saved.

The doubling of the SetView command tells wow to switch to that saved view instantly.
A single SetView command will slowly zoom to the chosen view.

Keyclone is not perfect for mouse broadcasting, but it gets the job done.
The Hurricane's probably won't overlap exactly, but they'll be close.
For PvEing down a pack of mobs, you can position the toons and then click the macro to open.
For PvP, you won't likely have the time to do this perfectly, but it still works decently.

I believe HKN can do mouse broadcasting fairly well.
I have recently switched to Inner Space from Keyclone, and know the broadcast works very well. Plus you can set any hotkey or click to broadcast not just a specific one. My druids broadcast Hurricane on 5 and Force of Nature on 4. With Keyclone, you'd pick to broadcast one or the other.