well you could do this with using hotkeynet and the toggle-command.
For example to /swapfocus with a press of 'j' you could use:
Code:
<Label w1 Local SendWinM WoW1>
<Label w2 Local SendWinM WoW2>

<HotKey j>
   <Toggle>
    	<SendLabel w1,w2>
    	<Key shift j>
   <Toggle>
     	<SendLabel w1,w2>
     	<Key alt j>
(here the window of ToonA must be named WoW1, the window of ToonB WoW2)

And bind the following macro on ToonA to j (with ToonB beeing the name of the other Toon):
Code:
/clearfocus [mod:shift]
/focus [mod:alt,target=ToonB]
And bind the following macro on Toonb to j (with ToonA beeing the name of the other Toon):
Code:
 /clearfocus [mod:alt]
 /focus [mod:shift,target=ToonA]