I think you could achieve it by addtemplating a second set of soldier mesh child objects (much like the animated head face object) and have it use a mirrored skeleton (as long as the skeleton can still use the same animations, it should work fine). I was able to get a soldier to animate with his whole body oriented sideways instead of standing up by accident when I was doing some alterations to the "default pose" of the skeleton. I had forgot to rotate it down back to the original location. So I think you can just rotate it so that it's facing opposite from the original rotation to achieve the mirror position and have a child object use that skeleton. As long as the skeleton is set up to use the same animation system of the soldier, then it should animate along with him.
But the main issue will be if the soldier is blown into the air or if he enters a second story or stairs or even so much as jumps up. At which point the second soldier would clip through the floor with him and ruin the illusion.
