I really think you need to ignore what Unreal says and just assume your values are correct.
Though I’m at a bit of a loss myself on how you would go about simple stuff like:
“adjust this wall by moving it by one meter to the east” - when you don’t really know what that means within the coordinates that Unreal uses.
Even with the widget reading out the conversion value for you, its pretty darn difficult to achieve the end goal of moving something to where it is accurate.
The widget will definitely help, and you’ll definitely get used to just knowing what direction etc, but the millimetric presion you’d get by re-importing Lidar defined objects will be near impossible to achieve by moving stuff by hand…
Really, I think you would be better off just re-importing the scene from the external DCC.
I would suggest you try doing so in a new project after you make the materials that the other project uses avaliable to it (copy and paste).
With the correct import settings your materials will be auto selected while each mesh imports.
I have a couple of temples built specifically to pass into different engines; the shaders in each engine are the hardest part to import just because there really is no standard (unless you evolve to HLSL and unreal isn’t friendly to custom USFs / still requires material instances and all that jazz).