I am not aware on any on device ones that aren't tied to a service (e.g. Ente does it on device because of E2E encryption meaning they can't do it on the server) but I think you need an account or to self-host the service.

There are options (other than ente) if you can self host, but (other than ente) the server will be doing the processing.

This one has a beautiful UI and does face-based grouping of photos: https://github.com/IacobIonut01/Gallery

Immich, but it needs the server side running somewhere.

Simple gallery (pro)

https://play.google.com/store/apps/details?id=com.simplemobiletools.gallery.pro

https://github.com/SimpleMobileTools/Simple-Gallery

(edit: didn't read the entire post like a fool. No facial recognition but still a solid gallery app)