Interesting, I had the same problem bit changed the renderer's Surface Inputs Diffusion Profile from "none" to "Skin". I guess it's just a different way of doing the same thing?

Hi Miranda, thanks for the update. Very much been looking forward to moving to 2019.3. Great news! Thanks. 

Hello~

This is Miranda from Reallusion.
Sorry for not helping in time, and it's good to know you've figured it out. 

There might be some issues with HDRP 5.7.2 itself, and this is fixed in Unity 2019.3 (HDRP 7.3.1)
We are now developing Auto Setup to be compatible with Unity 2019.3, and we can assure there will be no such problems in 2019.3.
Before Auto Setup is update, you may refer to the following steps to fix.

Make sure there is "SSSSerrings_Skin" in material profile.
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Change the Diffusion Profile (marked with 3) to "SSSSerrings_Skin", and select "SSSSerrings_Skin_Foliage" (marked with 4) first, then "SSSSerrings_Skin" (marked with 5).
If you choose 5 before 4, the display will be incorrect.
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I'm using unity 2019.1.14f1. My project also has HDRP v 5.16.1.

Something isn't working out for me, is this a bug? Something I'm doing wrong or not yet doing?
To minimize variables I put the following steps together to show my problem with just using the basics and stock material.

Create a new unity HDRP project, use the sample scene, so all the HDRP is already setup correctly.
Add in the unity setup asset found here (https://www.reallusion.com/character-creator/unity-auto-setup.html
Version 1.01 (Release Date: 2019-08-29)
From that zip file in subfolder "AutoSetup 1.01 for Unity 2019.1" I'm importing the asset package "HDRP.unitypackage", and only that one.

Now over to CC3. In Smart Gallery I open "CC Essential Morphs & Skin for CC3" pack, and load "Essential_Female.ccavatar"
Then I pop over to "Conforming Hair Vol. 2" and load on "Long Center Part.cchair".
And toss on some clothes too.

Then I choose: File->Export->FBX(Clothed Character)
With these settings:
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And then I switch back over to Unity...
There I am turn on auto-processing checkbox, drag whole folder of fbx export contents (*.json, *.fbx, folder.fbm, textures) into /Assets/CC_Assets/

After import is complete, I turn off the auto-processing checkbox.
Then I go into prefabs subfolder and drop the character prefab into my scene to check it out.
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Houston we have a problem...

Here is what the mask map and shader settings look like:
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Is this a bug? Something I don't have setup right, or doing wrong or need to do? 

In another post someone mentioned the fix is turn off transmission. But that does not solve it. It makes some improvement but does not fix.