If I’m not mistaken, the upcoming version of iClone will provide export features to the UE4 skeleton, along with already present import features for DAZ characters. As far as I understand it, using those two in your pipeline, you will be able to create characters in DAZ, bring them to iClone, animate (e.g. facial expressions, lipsync) if needed, and export them to UE4 with the epic skeleton layout (+ blendshapes).
There’s also the Character Creator for iClone, but compared to DAZ it seems to have a long way to go still, especially content wise.