dnd 5e – Can the invocation of the blessing of the blessing of the Queen of Raven Raven of the AU be used by a sorcerer to heal and awaken an ally to 0 HP?

Yes, the Blessing of the Raven Queen can be used by an Unconscious creature

As a face value, Raven Queen's Blessing simply enables spending a Hit Die. It's a completely different way to activate this than a short break.

There is nothing in the Unconscious state that prevents this from working.

Of course, Uncarthed Arcarna is game test material yada, yada, yada.