Certain Library Objects can be flipped or mirrored in Lumion 2025 and newer versions.

This can be done by selecting the Object and clicking on the Flip button in the Advanced Properties panel. Multiple Objects  can be flipped at once.

This is especially useful for positioning non-symmetrical Objects like sofas and couches. 

Or, for Projects with cars that need the driver on the other side of the vehicle. 

Note:

This option is only available for Content from the Transport or Objects categories.
For Imported Models, please use your 3D modeling software before Re-Importing your model. 

See Also:

• Learning Pathways: Content Library
• Knowledge Base:  Lumion 2025.0: Release Notes