Additionally to use rotation, scaling, mirroring…you can also use the separate material ID’s options for the static mesh’s collision: In this example the outer “fassade” and inner “center” material ID’s were unchecked for “enable collision” (and cast shadow), so Unreal does not take them into account for creating the collision. As you can see the resulting “hole” only uses the frame’s material geometry for calculating the collision:
Then use a 100% transparent material in these materials slots, and you can create different geometry with proper collision out of one and the same mesh. Here some variations and combinations as example:
TrusshapeB.fbx (179.8 KB)