Yes,
I’ll hafta do this from memory…currently building HLODs
Right click on Content Browser and add, I think its in Miscellaneous > Data Asset
then choose Building texture data… or something similar
It will create a new object in one of your project folders in the Content Browser.
Double click to open it, then you’ll be able to drop your material in the Material Override slot.
Save and Close, then you can drag the new texture data asset into the Primary and Secondary slots of the prop.
Sometimes the material won’t show on the prop, so I usually add the material that was used in the override material slot, on the props static mesh component as well.
Most props have an allow Custom material setting which needs to be ticked, either in the props settings or its static mesh component settings.
There is also the breaking effect, when the prop is damaged. This effect is a material property and if you want this you have to use an instance of the MI Fort Parent Base material (or a similar sounding name, which I can’t look up yet…but you’ll find it in the Fortnite/Materials folder somewhere)
and add your material stuff to that. It works a bit differently to the materials editor, using settings instead of the node graph.