Blender and game engines

Blender and game assets are Y-up and in meters; CAD expects Z-up millimeters.

You want	Use case
Props, cosplay and game assets in CAD	Export GLB, then convert with meters and the right up axis; add mounting features in CAD
Kit pieces as separate parts	Split a multi-body mesh
A sculpt or export that won’t convert	Repair the mesh

Tips

• Prefer GLB: its up axis is known, so only the units need setting. For OBJ and PLY from Blender, set Up axis › Y (--up y).
• Organic models stay faceted in CAD; decimate them in Blender first if the STEP is too heavy.