It seems like the player models specifically are too small. The world geometry, models and meshes seem to possess relatively correct scale in relation to eachother. Example:
According to Wikipedia, a MG-34 is about 122cm long (44'') - What size would, then, be that german soldier? Seems like the size of a child to me.
This can be seen on some old media, too:
Assuming the Mkb has similar dimensions to the StG 44, its length is about 94cm (37'"). How tiny is that german soldier, then?
Larger characters would instantly improve the fidelity/scale, but it's probably not that simple of a decision. Larger characters = larger hitboxes, there are gameplay consequences to think about, and by now it's probably too late to change. It does appear very wrong as it is, though.
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