Echoes of Great Sundering Macro

Hi guys,
I’m kinda new here and I have a quick question for you.
I’m actually try to create a macro with the new elemental shaman legendary “Echoes of Great Sundering” that say “When you cast Earth Shock, your next Earthquake will deal 175% additional damage.”. When you’re equipped with this legendary, whenever you cast an Earth Shock, you get a buff called “Echoes of Great Sundering” on you. On WeakAura, it’s possible to use this buff for create specific results, but I don’t know if it is possible to make the same with GSE variable options. The goal would be to cast Earth Shock, and when the legendary buff comes, you’re next use of this macro would be Earthquake. I know that macro link with buff doesn’t work with classic WoW macro, I’m just wondering I it does with GSE.
Thanks for your answer.

In the end I created this macro:

/castsequence [@cursor,nochanneling] reset=15) Earth Shock, Earthquake

That work pretty well, If that can help some people :slight_smile: