I'm creating human figure in Adobe Fuse/Mixamo. I open them in C4D and attempt to make adjustments to them. So far I've been able to successfully make arm and leg position adjustments. However, I've not been able to make facial expression adjustments. Any suggestions how to do this?
When you say adjustments do you mean alter the geometry or animating them with bones or morph targets?
There was another user that had issues with this pipeline and I wondered how you were getting on with it and if there were any tricks - they were getting massive file sizes when animating in Fuze and bringing that into C4D for rendering.
As for facial - you can put bones in the face (or more correctly animation nodes) and then you can paint weights to control how much influence each node has on each polygon. You can also use morph targets. You position your animation nodes to get the expressions you want and then take a snapshot of that expression. Then you can smoothly transition from one snap shot to another.
I don't think Mixamo generated bones for facial stuff unless there is a specific "face" model they have that I haven't seen yet. ( I gave up on Mixamo when adobe bought them and left us all stranded for a few years).