This would be an NPC stood on the platform while passengers board your train, as boarding finishes they’ll flash a green signal (previously a flag but now an LED display). Train dispatchers don’t have to be at every station but appear at stations that do have them in real life. There could be possible scenarios where the dispatcher doesn’t give the all clear forcing a delay in departure.
Also have them blow a whistle when it's time to close the doors and again when the doors have shut and the signal is green. Also some railway stations still use Flags and battons. Glasgow Queen Street and Glasgow Central usually uses them as well as alot of the other stations in Scotland. The gaurd on most services usually carry a flag and whistle for that very reason to dispatch the train where no Dispatchers are available. Very good idea! Have already suggested it myself!
Yes it would add to the proper railway atmosphere along with removing the door close operation from the driver on traction where it is not their responsibility.
I would love that idea! However, remember how robotic and rigid NPCs behave currently in the game. This would require to implement some special movements and poses with arms and hands (waving the flag, gettint out and blowing the whistle etc.), then the need that the NPC is placing itself correctly in order to see him from the cab (in case of the LED or flag). To be honest we are far far away from that.