XYZ To UVW is also known as planar projection or flat mapping. This mapping type takes the coordinates in world or object space and uses them as UVW coordinates. For images, only the X and Y coordinates are relevant, which are mapped to U and V. In other words, the images use flat mapping projected along the Z axis. XYZ To UVW results vary, depending on whether it is applied to a Procedural texture or an imported texture. In Figure 1, a procedural texture using XYZ To UVW is oriented in a similar fashion to Box projection. In Figure 2, an imported texture using XYZ To UVW is oriented in a planar fashion. The following images are from the Standalone version of Octane.
Figure 1: XYZ To UVW projection applied to a Procedural texture map
Figure 2: XYZ to UVW projection applied to an imported texture map