That is an interesting tool.
Being curious, I tried using Google's image search and struck out on an exact match, but it found some similar hammers used for blacksmithing.
I found a web site that outlined "types of hammers" and based on this, it looks like some kind of embossing or rivet-setting hammer.
https://www.mechanicalbooster.com/20...f-hammers.html
I'll be interested in hearing what you learn, whether it is an artisan-type tool or was a commercial tool for riveting or manual shaping.
Good luck!