Yea, well at least I found this thread here. After 2 days.
Now I know that further research in the matter is useless. At the very least this must be mentioned in the documentation of the clothing tool. Just like the fact that you cant use more than 16 collision objects on a mesh with clothing!
I mean people expect certain functionality and if Unreal does not provide it the least you can do is write about this clearly in the place where people get their first information from to save us frustration.
I would settle for a way to edit a clothing information nd then be able to transfer it over to another skeletal mesh that has the morphs baked into it, since I have a small number of fixed body morphs and would be willing to export them baked from my 3D application but it looks like not even that is possible.
Instead, the only possible solution now is to export each bodymorph baked and then do the clothing painting again and again and again on each mesh.
That really sux!