Hi
We managed to find a solution. Since there is the possibility of differences of scale between the components of metahuman (Body, Face, etc), Hair, fuzz, eylashes and any kind of groom attached are hierarchy binded to their parents. So you have to change the Bounds Scale of the Face (or body, if there is any groom attached to it) at blueprint, if you do it at scene, you’ll have to overwrite the blueprint before save, or else it will lost the setup.
Here we changed from 1 to 100, it worked perfeclty, we were facing this problem using the cinematic cameras + sequencer + render queue. So It’s possible that it is the same problem at play / rendering / packing time.
Please let me know if it works for you guys
Hope It was helpful!