Sony do not publish the formulae for their Hyper Gamma curves, as far as I am aware, so there are no IDTs for them. In addition, Hyper Gamma settings do not lock the user out of making various in-camera image tweaks, in the way that the S-Log modes do. Hyper Gamma is really display referred, and adjusted by the camera operator to “look pleasing”, so it is not really possible to invert it to true scene referred.
At least that is my understanding. Anybody who knows better please jump in and correct me.