Did you never play War of the Lions?

The name changed in that to Judgment Blade, and you can see above she has that skill.

No STATIS BLADE. Yeah, cause the skill is called STASIS BLADE (or Judgment Blade as the guy pointed out).

Actually it is stasis sword, sometimes mistranslated to "steady" sword

It confuses me too, it suppose to be a unique skill to Agrias but Delita also uses it...

What makes you think it would be unique to Agrias? Judgment Blade is an ability usable by Holy Knight, Rune Knight, and Sword Saint. Delita is a Holy Knight in fft, Orlandeau and Dycedarg also can use the ability.