I've been using a program as simple and simplistic as Windows Photo Gallery since about the last 10 or so years with facial recognition.
In the beginning I dismissed it as cheap thrills, useless bloatware .. but after Nikon stopped support for ViewNX2, I had to look for alternatives to keyword/tag my NEF files.
Problem now is Microsoft have also stopped support for Photo Gallery as well tho .. so I'm back to where I started.
Reason for using Photo Gallery is that it embeds the keywords/tags into the NEF file(my preference), and once done, it's then synced with all my other software so that the NEF file's keywording/tags are seen via all programs used to open the NEF file.
For a long time I hadn't used the gimmicky facial recognition part of the Gallery software thinking it's silly, but about 3 years ago I had many old photo scans of my mother, and began to keyword them.
it then offered to use the auto facial recognition tools, located images of mum, and asked me if that was 'mum'. Accepted, and tagged those that were mum .. job done easily, and much quicker than I having to sift through images to find.
Tool made me laugh tho when I had an image of my daughter with he cabbage patch doll, and it located my daughter well enough but then asked me who the cabbage patch doll was.. gave me option for mum, my brother, and a host of other people I'd located earlier.