For one, going to war barefoot was not at all something unheard of. Within the area of modern Southern China/Nothern Vietnam, the soldiers always went barefoot. Take the "Asian" guy and remove the boots.
That's a reasonably accurate depiction of a soldier there. Same thing also happened in Europe. Irish always fought barefoot. Even in armor.
Specifically these warriors are not particularly accurate. They play up stereotypes as needed. Like how the Egyptian soldier carries a khopesh not because research supports it as a weapon used in mass warfare, but because it screams "Egyptian". The African armor also looks like a hodgepodge of various styles and artifacts from across all of history, rather than an attempt to reconstruct an Aksumite soldier of the period, whom were in active contact with the rest of the Mesopotamian (Western) civilisation and most likely used very similar gear to everyone else like the Yemeni soldier here.
But that's not "African" enough so you instead pick out a weird sword, add random golden bracelets, fantasify the armor a bit. To make him stand out as "The African" of the bunch. Readability over history.