I figured it out, when converting character to game objexct you need to select the box separate eyelash from body mesh. This

From the looks of it the Opacity maps are missing for the eyelashes.

I don't use the Unity pipeline so I don't know how you could fix this.

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I converted my cc3+ character to game conversion menu, replaced the eyes and mouth with game objects. I exported out and downloaded the cc4 to Unity asset. I’n Unity after building materials my character eyelash is wrong. I have brought in characters before to Unity doing the same steps but never converted to game conversion