This hints toward the fact that Collei should be coming soon in the game.
According to a leak posted by Save Your Primos, which is quite a credible leaker in the Genshin Impact community, Collei’s skills are done and are still being tested.
There are other playable characters such as the Archons, Traveler and Dainsleif who are without a Vision, so this isn’t quite unusual as such.
However, it is further stated that the Vision situation of Scaramouche is not known as of now.