While CONSTELLATION is running, I checked out the German Netflix series THE SIGNAL, which is VERY close to CONSTELLATION in premise. Except for a different mystery at the centre, and - I have to say - an extremely unsatisfying resolution.
I've added the Netflix series 3 BODY PROBLEM to the list, but I'm really, really struggling to get into it. The first episode is so excruciatingly boring. It's only about an hour long, but I've already had three sessions, and I'm not even through. Does it pick up?
Meanwhile, CONSTELLATION -- as previously mentioned -- is a good show. The different realities are a bit confusing at this point, but I suppose that's the idea with such alternate reality shows.