Uli, Resolve's Face Refinement is Studio only I think... I can understand some would like to find a cheaper way to achieve it. Unfortunately, I don't have a Fusion specific solution (excpet Sander's one now, thanks to him), while I have half a dozen very efficient in Resolve (excluding Beauty Box ofx or some Boris ones I could use)...
*MacMini M1 16 Go - Ext nvme SSDs on TB3 - 14 To HD in 2 x 4 disks USB3 towers *Legacy MacPro 8core Xeons, 32 Go ram, 2 x gtx 980 ti, 3SSDs including RAID *Resolve Studio everywhere, Fusion Studio too *https://www.buymeacoffee.com/videorhin