The Focus -> Inspector option has several filter choices. One of which is Identified. I have never found this very useful, but I often wish there was a way to find the albums that are unidentified, so that I could check if perhaps some of those albums now can be identified.
The focus filters can be inverted by taping them, so all you have to do is focus by identified (green icon), then tap it so it becomes a not-identified (red icon).