Face unlock is the new hotness and HMD wants in on the action, so in the coming months it will add it to its high-ranking phones with an OTA update. The following models will get it: Nokia 8 Sirocco, Nokia 8, Nokia 7 plus and Nokia 6.1.
Considering the hardware present on these phones or rather the lack thereof this will be a pure image recognition system. If implemented well it can be convenient, though it doesnt offer much security (unlike biometric methods).
Nokia 8 Sirocco Nokia 8 Nokia 7 plus Nokia 6.1
As for the rest of HMDs Nokia lineup, nothing has been confirmed yet. The Nokia X6 seems like a good candidate, the others may be disqualified based on chipset (for fast unlock times, a good CPU and ISP are needed).
Source | Via