To import a 3D model with texture atlases without Blender, use tools like Unity, Unreal Engine, or online platforms (e.g., Sketchfab) that support formats like FBX/OBJ and handle atlas-texture linking.
These tools either auto-recognize atlas references in the model file or let you manually assign the atlas image to the model’s UV maps, ensuring textures display correctly.
If your model and atlas are separate files, keep them in the same folder before importing—this helps tools connect them easily.