Or how about implementing some basic 3d program features in UEd, so people can make their models there where also all the other assets are already. then you dont have to buy/learn an separate 3d programm and dont have the pain with export/import problems.
Epic would not even have to develop such simple 3 d features, there are a lot of free or buyable 3d engines out there.
Autodesk will not love this, but the community will love Epic for this.