Atziri's Rule MTX? Is there a way to change it?

Hello!
There is a question - how to change MTX on a queen's demand skill for Flames of Judgement and Storm of Judgement?
My guesses are that i need to take flameblast gem → put it somewhere (may be in staff) → open MTX menu → change the appearance of it → get flameblast out.
Will this method work?
Same with a storm of judgement aka stormcall

It would be easier to fight Atziri when your flameblast is different from her.

I tried to find any info about it but fail.

AFAIK, skill gem effects are applied to the gem and not the skill. So applying a Harbinger MTX to a flameblast gem will affect that skill gem when used, but not any other flameblast gem that you have equipped; you can apply a celestial effect to a second flameblast gem, and then equip Atziri's Rule, and have three different flameblasts on tap that all look different from each other. I think. I haven't tested this, BTW, because why waste the sockets, but I think that's how it works. So, no, I don't think you can use Atziri's Rule in a fight against Aztiri herself and not have the visual confusion you're describing.

Playing it in Phrecia event. Thinking of same.