Pretty sure we see the pyramids in the screenshots so it's in the game. Sphinx might be a unique building
Guess I wasn't clear enough - I know the Pyramids have been confirmed in-game, and I think we're pretty much all certain they're a wonder. What I was observing is that, while we know the photos of the Sphinx, the Forbidden Palace, the Colosseum, and the Great Wall in the trailer correspond to "two unique improvements and two wonders", we don't know if the picture shown in the trailer actually 'counts' as the Sphinx or if counts as the Pyramids (as technically both are visible in the photo).
Ergo, the question remains: if the Sphinx is being referenced, I think it's safe to assume that it's an Egyptian UI and the Great Wall is a wonder, while if the Pyramids are being referenced, then they're the second wonder and the Great Wall is a Chinese UI. There seems to be little doubt that the Forbidden Palace is a wonder and the Colosseum a Roman UI, but that's only half of the statement 'decoded'.