Some people have pointed out that this could be Jenna Coleman as Lady Johanna Constantine in the behind-the-scenes sneak peek for The Sandman season 2. The woman in both pictures sort of looks like her. The picture with the heads in the cellar looks like it is a scene from Thermidor, which is where Lady Johanna Constantine canonically appears again!
We'll have to wait and see, but I agree that this is indeed likely to be her!