create 3D grass material and assign it to an imported objekt from revit as a ground

i want to create a material where i can spawn grass as a texturwe to an imported surface which i imported from Revit via datasmith into unreal 4.27
Is this possible or do i have to paint over the area with the foliage tool? As far as i have seen mostl automatic grass is only possible with landscapesurfaces.
Any Hint or idea or am i completely wrong?
Thanks in advance