#showtooltip Enveloping Mist
/castsequence reset=target Soothing Mist, null
/cast [channeling] Enveloping Mist; Soothing Mist
Is it possible to turn that into a help/harm macro?
Those would both be helpful spells, so no, it would not work like that. However…
/cast [harm] blackout kick
/cast [nochanneling:soothing mist, noharm] soothing mist; [channeling] enveloping mist
Does allow you to tie the two together, and add a harmful spell to it.