Diana, Steve and Joe walk down the hallway and Diana puts a card in a slot to open the door. The door opens and through the crack on the left side of the door, there is a man behind the door who opened it. After Diana and then others enter the room, the man behind the door closes it. In the next shot, from inside the room, the man is gone.
Hitler is cloned as an adult human. Somehow, he has all his memories of his history. Even if that is overlooked, he doesn't speak German, he speaks English, with a German accent.
After Hitler is brought back to life he addresses his troops in English. Hitler spoke German, with a heavy Austrian accent, and may have know some French and English but would never have spoken to his troops in anything but German.
When Wonder Woman apparently stops the tank, in a head on angle you can clearly see the tank treads are not moving, yet the continuously move from the side angles.
The helicopter used clearly shows a US "N" number on the belly and side of the helicopter.
At one point Wonder Woman is hiding watching the helicopter land. When the camera is behind her she is behind several trees and a bush and is well hidden, when the camera is in front facing her she is behind a single tree and partially exposed.
Steve asks Diana if she can read German and she replies "yes" yet her lips do not move.
When we enter the Doctor's cloning lab for the first time, watch the top right of your screen to see the shadow of a camera on a crane slowly drop into view.
When Hitler is slowly being recreated we see a shot of his boots moving as his body reforms. It is clear a thin peice of wire is pulling the boots to give the impression they are being filled with Hitlers feet.
The vehicle Dianna Prince identifies as a tank is actually an American M113 armored personnel carrier. Also, it could not carry a gun mounted in a hatch cupola as shown, a turret would be required.
The vehicle Steve Trevor identifies as an armored car is actually an American M3 half-track with a turret.(likely fake)