How to activate this Skill on Valkyrie?

[coldreactive]

While on a Trial Valkyrie Character, I can't seem to activate the "Judgement of Light" skill on Valkyrie. It says to use LMB or RMB after another skill, and I've done that with various different skills to no avail. I have had the SP to do so, so that's not the issue, and it's not on cooldown since I cannot use it.

https://s1.pearlcdn.com/NAEU/Upload/Community/a927f0a0fab20230825211511445.png

I also asked on the Discord's help-and-advice channel.

[Zen]

the way it works is misleading, you have to activate the skill then press Lmb or Rmb when the animation starts, short term animation cancel