You could try Darktable. It's an open source RAW editor app and according to the documentation it opens ORF files.
Just as an FYI: Raw support has to be added on a camera model by camera model basis. The ORF produced by an an M5 is not the same as an M5 mkII. One of the defining characteristics of each camera model is the raw it produces.
Raw files are not actually files in the same sense as a .Docx is or even a .tiff. A Raw is a sensor dump from the camera, and as that is a product of the output from the sensor and the camera firmware, each model is unique.
So again a key question is the model of the camera, not just the brand.
There are multiple raw processors: Photos, Lightroom (both versions) Capture One, On One Photo Raw, DxO Photolab as well as open source ones like Darktable, RawTherapee. Some rely on OS support for the raws, but most have their own support. This is usually delivered faster than Apple do it.