Guidline to externally modify the metahuman body?

Hi does anybody knows if it’s there a documentation or some guideline to about how to modify the skeleton bone position of a metahuman skelton inside maya and reskin without going crazy?
Metahuman has this awesome face but the body choices are pretty limitated and the details of the geometry is not so accurate… I would like to modify the body shape to have a good pipeline between marvelous maya and unreal.
I tried with the Idea of a fullbody morph Target but when it comes to maya the blen shape appened befor the skin cluster so it’s not ideal for a full body modification, then I have to reskin the modified body but I have to move the joints to be correct in deformation. that is a pretty big deal speaking of metahumans, even if I’m not a begginner in rigging.
any suggestion?