Yeah only need it apply the modifiers to the original .blend 
there is a way for change directly the entire armature?
example= tall character armature
default character
short character armature
dwarf character
I don’t think so, because this would affect weightpainting as well as placement of bones which I don’t think you can do in real time. Its probably best to have seperate rigs and just spawn them in.
You can exchange the entire armature. But this means you are exchanging complete object tree.
Skin meshes have to be bone-parented. You can’t bone parent within the BGE. Therefore you can’t parent more “cloth” or “skin” objects to any armature. The number of skin meshes is static an can only be changed within Blender (not the BGE).
That is the reason why I suggest to bone-parent mesh object without vertices as placeholders. They do not eat much processing and you can exchange the mesh via Logic Bricks and via Python (whatever you like).
The downside is they are a bit hard to handle with Blender as they are nearly invisible (just a dot). You can enable Name and Axis at the Object Tab/Display Panel.