I know [target=focustarget] and [target=party1target] are valid arguments. I went from the former to the latter.
Maybe try something like this.



#showtooltip Healing Wave
/assist Ognian
/cast [mod:alt, target=player]Healing Wave; [mod:ctrl, target=Ognian]Healing Wave; Healing Wave

Assuming Ognian is your active character and Hoofu is the background toon...
You can have your healer self-heal with alt, heal Oggie with control or heal Oggie's target otherwise.