Interactive realtime Blender data import and export for fusion would be lovely feature - fusions own render engine is pretty old and legacy kind of stuff that would be better replace and this why having blender realtime import for fusion would be lovely feature. Unreal is having option that will transfer 3d data between blender and unreal in "realtime"/interactively. Other option would be having unreal kind of integration - they might even grant epic grant for this kind of job if black magic will contact:
https://www.unrealengine.com/en-US/megagrants (they have granted it for few commercial companies and products like maxon / c4d - already for similar purpose - to make unreal more flexible).
Also nvidia's omniverse can import and export data between multiple different apps/softwares so this is going to be pretty common in future i hope. By using USD format i guess.