If this drawing of King George V, accompanied by his eldest son Edward Prince of Wales (the future Edward VIII), visiting British troops on the Western Front in 1916, resembles a photo in any way, it is entirely due to the skill of the artist, Fortunino Matania.
Matania was famous for his realism, and his World War One drawings scored over photographs of that era because they didn’t look staged. If this had been a photo, most of the people in it would have been staring nervously at the camera!
Original drawing.