I have still 4 shaman in LK and have a macro for them. when i click button 3 they heal each other. I will write macro but you can write your character names instead of "Type your Char name". And don't forget that macro limit is 255 so edit this macro on text editor and copy them .
This macro for 5 characters healing wave spell if you want you can change spell
/castsequence [@Type Char name] Healing wave,0,0,0,0,0,0,0,0
/castsequence [@Type char name] 0,0,Healing wave,0,0,0,0,0,0
/castsequence [@Type char name] 0,0,0,0,Healing wave,0,0,0,0
/castsequence [@Type char name] 0,0,0,0,0,0,Healing wave,0,0
/castsequence [@Type char name] 0,0,0,0,0,0,0,0Healing wave