Why does material on imported Runtime Mesh Component look bad?

Hello, I was trying to import a FBX 3D Object with Assimp und runtime mesh component into UE4. It creates a runtime mesh component without any Material. I importet the material separately into the editor.
The Problem is as follows: After that I created the runtime mesh component I’m using the “Set Material” function in my blueprint to use the separately imported material on my Runtime Mesh Component.

For some reason the material looks bad without any detail. Only the color seems to fit.
When I use the “import” button to import the fbx file into the editor, the material looks fine, even though the same material was used. The size differences don’t matter here.
Objects in game.jpg

I hope, you can help me to solve that issue. Please recognize that I’m an absolute beginner so please try to explain it on a low level.
Thanks for help, Niclas

Hi. Did you find a slution to this? I’m facing a similar issue after importing a skeletal mesh at runtime using the RuntimeMeshLoader plugin. I’m not able to import the material from the fbx.