In USA I don't think it is because the end use is transformative [1].
In UK it would be tortuous because it relies on Fair Use to temporarily store the images in order to extract the facial structure data. Fair Dealing is really draconian in comparison.
And it's our job, as someone who knows what a computer is, to move forward with common sense if they're overreaching which, is their job.
They have every incentive to be as conservative in their advice as possible, and no incentives to "allow" risks. Doesn't increase their compensation any.
In UK it would be tortuous because it relies on Fair Use to temporarily store the images in order to extract the facial structure data. Fair Dealing is really draconian in comparison.
[1] https://www.lib.umn.edu/copyright/fairuse