I have the feeling this could be Scarlet:
Inquest, Bandits and Nightmare Court are forming an alliance in the events of Brisban Wildlands. She could have joined such organisation after her appearance in the personal story. She would have enough reason to spoil everything the queen is doing and that vandalized Queen's speech announcement would fit her.
Those alliance could possibly be the root of the Aetherblades, at least this is what I thought when I first heard of them, but then there were Charrs and Norns among them.
Since the living story is going to be tied together somehow, my money is on Charr and Norn refugees from the Flame and Frost / Southsun Events having joined these forces.