This is a major overhaul from me.
I modified the export/import script so now it will consider whether you export/import high res. or LOD geometry.
That means you won’t get displacement shader and there is no subdiv for the highpoly version of the geos.
Also, there is no subdiv and the Displacement intensity is 0 by default for the 3D Plants as well.
And a few more tweaks.
Install:
Download then replace the two original file in your Megascans\Library\support\plugins\maya\6.9\MSLiveLink\Megascans
folder.
ImporterSetup.py and Renderes.py
Download: https://github.com/ddankhazi/megascans
Tested with the current 6.9 version of MSLiveLink.
Recommended download settings for Quixel Bridge:
Recommended export settings for Quixel Bridge:
Use the same texture settings for all asset types.
Surfaces, 3D Assets, 3D Plants, Decals, Atlases.
For models this is my recommended settings:
This way you’ll get high resolution models.
If you want the Displaced version turn off the Highpoly Source option.
Of course, you still have to fix the Displacement textures (see my previous posts, R -> RGB issue and incorrect offsets).
note:
I could not test the Redshift version in render.
Also, if you have any issue just write a comment.
Cheers, D
Denes Dankhazi's Blogfolio 
Hi, I ended up here because I’m trying to get the correct look for Quixel objects for Redshift in Cinema 4D. Do you know if I could do a port of your solution in order to work with CD4?
Thanks mate!
I was having similar issues in C4d/rs.
My best results were obtained with adding a color correct node before the displacement node, and setting gamma to 0.3333 and contrast to 0.6666 and perhaps playing with the amount of displacement in the redshift object tag.
And in the displacement node, setting the “old range min” to something like 0.6666.