That's NZXT Cam if i'm not mistaken. Which is just "CamApp 3.0" try looking that up.
This is a nice looking overlay. https://camwebapp.com/
Yeah tempted to try it myself i've never actually used it just seen it. I just use MSI Afterburner which does pretty much the same thing but not average/min/max FPS just current. But that doesn't really bother me unless i was benchmarking/comparing it might be helpful.