There’s some great addons that make the work between Blender 2.80 and Unreal 4.21(4.22 soon I’m sure),
Is the addon for the Blender to UE workflow:
For PBR from Substance to Blender to auto connect nodes:
I’m sure the above would eventually be added to your workflow, so they sort of go hand in hand.
The ultimate question is, will there be a smooth transition between all three, at least. If so, then I know I’d be a happy camper.