From LibRaw:
In order to streamline the workflow with the raw shots taken in the new Pixel Shift Multi Shooting mode offered by the new Sony A7R-III camera, and provide a way to use popular RAW converters (Adobe Camera Raw/Lightroom, Capture One, and some others) for processing these shots, we’ve developed the SonyPixelShift2DNG application, which converts Sony A7R-III shots taken in Pixel Shift mode to DNG, supported by most (but not all) programs that process RAW files.
SonyPixelShift2DNG performs the two following tasks:
The resulting DNG files can later be processed in familiar applications like Adobe Lightroom and Camera Raw, CaptureOne, Iridient Developer, Luminar, and others.
This is time-limited beta version. It will expire on May 01, 2018
Mac OS X/macOS 10.6 - 10.13, 64-bit: SonyPixelShift2DNG-0.8.0.29.dmg
Windows 7-10/64 bit: SonyPixelShift2DNG-0.8.0.29-x64-Setup.exe
System Requirements
* There is no 32-bit version right now: to work, the program needs 700+MB of free RAM, which is unlikely on a 32-bit system.