but the version we have circulating is the EvoBus version.
EvoBus is the subsidiary of Daimler which manufactures the buses. The version made by Alterr is just older than the one you are showing.
It differs in some ways, like the front doors also have a door alarm, Red LED Matrix for the passengers (with the STOP - PARAR line displaying above the Bus Stop name)
This can be modified (door script, sound CFG and audio files, replace interior display with your own model). You have to dig into the matter though. Maybe there is already a mod that implements red led interior display. Let me know if you find it, I'd be interested, too.
LED Matrix outside
There are mods available for this bus which implement this type of matrix using Krüger++ or Busfanat's matrix.
I really wanted to have one like this in my collection just to show it to you
The one in your photo is the facelift version of the Citaro. Even the outside differs quite a lot from this one. There is a facelift Citaro in development by the people who are building the map Mainz, you can see WIP pictures in the german presentation forum.