@Gewehr98: I also had family fight as Doughboys during WWI. It's good to hear you're taking care of history.
@Danik: Yes and no. The picture is more of an assortment of WWI German items put together on a mannequin rather than an actual impression.
Here's a photo of a Grenadier from Grenadier-Regiment (5. Württembergische) Nr. 123. The Württembergers had unique ammunition pouches, many would recognize as medic pouches in WWII. Also, he has the Swedish Cuffs worn by certain units.
Then here's a picture of two Stosstruppen.
These are much better reference pictures. If there's any particular units that you'd like to see as German, I have a ton of pictures.