Q. If a model suffers damage from a Trigger, is that damage considered to also be from the Action that generated the Trigger?
A. Yes. Effects from Triggers are additional effects of the Action. Thus, Abilities such as Incorporeal that modify the effects of certain Actions would also modify the effects of their Triggers.
Q. Sonnia Criid - Does Incorporeal reduce damage from Sonnia’s Scorched the Soul Action?
A. Yes. The damage from Scorch the Soul is both from the Burning Condition and from an Attack Action. Any modifiers from both sources affect the Action (such as Incorporeal and Flaming Body).