Since this feature is new, I do not know exactly, but I have a small idea about it.
As far as I understand, this feature is not a wrinkle in the sense of old age.
For him, old age morphs can already be used.
I think this feature is related to the lines formed on the face according to the facial animations.I'd say wrinkles appear when the character is imported with morphs and you change the morph settings in the skeleton properties. In other words, wrinkles become apparent only according to facial movement.
As you said the crease doesn't work when transferred to UE with iClone and I wrote this in the iClone thread. It only works if imported with fbx.
The other point I found is that if you change the character wrinkle settings, you need to transfer the character back to the UE.
So the live link doesn't seem to have anything to do with wrinkle.
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