Changing the static Mesh of Items displayed by the item placer

Hello there!

I have been looking everywhere to find a solution to my problem. I see it pretty often on creative maps that they use the item placer but change the mesh of the item placed (see picutre). Whenever I try to change it, uefn does not allow to change it nor can i use SetMesh() on the Item Placer. Do you guys have an idea?

Thanks!