Thanks @Evgeni_Popov and @labris!
Yes, it’s looks way more like the reference with pbr marterial. And edge rendering plays definetely the most important role that the model looks like a drawing. I adjusted some parts of the cad in blender, added metallic pbr and enabled edgeRendering.
The result looks promising. But as you mentioned Evgeni the edgeRendering isn’t perfect - some lines are missing and sometimes there are two lines next to each other. What’s the best way to improve the edgeRendering? I am sure that the babylonjs team has created a way better script than I could. So manipulating the edgeRendering.js wouldn’t be very effective.