None. What part of “Blender’s OCIO config was designed for a srgb output and a linear rec.709 reference” you don’t understand?
And what is your point again? That you can’t do what you want with OCIO?
Because it’s actually that you can’t do what you want with that config, hence you need a different one.
Now, if that was an unorthodox way of asking for help for producing your own OCIO config, then apologies. I can help you with that when the time comes, but you really need to wrap your head around the model first