Lens undistort best ways in stereo 360

Is there a tutorial to use the mocha pro tool Lens : undistort for stereo 360 to take out the nadir point easily.

Yes, check here, this goes over many Mocha VR features, but shows how to clone paint in the Nadir using the lens:undistort and distort options in the Mocha Pro/VR plugin: Boris FX | Mocha VR: Object Removal

Let me know if that works for you.