Face thumbnail contact sheet, collage or print

When I look at the faces for a person in Digikam (many faces in the People view), I often feel like I would like to create a contact sheet, collage or multi-image print with just the face thumbnails of that person from several images. In other words, it is the recognised faces showing in the People panel, not the whole images in which these faces are found, that I would like to use and put together in a multi-image contact sheet or collage.

I am only aware of the mosaic plugin, but a) that ony uses whole images, not the faces and b) I am not (necessarily) looking to create a mosaic, though for people who I have thousands of images of that might be a nice idea, too.

Has anyone worked on a project for a plugin like this, or seen any solution through which I could achieve this?

Just added a supporting comment on a related feature request in the KDE tracker.