I am the developer of PhotoFlow (https://github.com/aferrero2707/PhotoFlow), and editor for RAW image files. It supports OCIO via a dedicated tool that can load a given configuration and apply the available color transforms. So far the tool has been tested it with the Filmic (https://github.com/sobotka/filmic-blender) and ACES (https://opencolorio.org/configurations/aces_1.0.3.html) configs.