The software is essentially a viewer for the in-camera Raw converters that already exist on X and GFX series cameras. Fujifilm claims that X Raw Studio is more than twenty times faster than the SilkyPix-based converter. The macOS version is available for download today, with a Windows application to follow in February.
The software adjusts exactly the same parameters as on the camera and supports batch processing and saving conversion profiles. As of today only the GFX 50S and X-T20 are supported, with the X-Pro2 and X100F to follow in December, all via firmware updates.