You can set the Viewer LUT to linear, and add an OCIODisplay node just before the viewer.
See the following screenshot:
- viewer 1 applies a standard sRGB LUT
- viewer 2 applies no LUT (linear), and the OCIODisplay node is set to RRT/sRGB, as defined in the default (blender) OCIO config
Note the GPU render is disabled by default in OCIODisplay, because GPU Render is not considered accurate in OCIO (see this OCIO github issue) but if it’s just for display you may try to enable it (not: there may be also a Natron bug when GPU render is enabled)
There is no way in Natron 2 to add your custom color colorspace to the list of display luts in the viewer.
Does that answer your question?
