What is the fastener?

I know a typical screw and nut in a pair of scissors will not align the blades well enough. I want to understand what kinds of hand finishing processes might be used to remedy the alignment problem. Like is this pictured example using a wave or crush washer to compensate for the alignment variation induced by the thread helix and pitch clearance, or something else likely going on? Does this kind of fastener have a name? Is there a more general variant with wrench flats on both sides or does this design typically require a more involved tooling to create?

In other words I want to have an abstract understanding of the entry point, nuances of application, and investment required to incorporate the design into other DIY type projects. For (a rough) instance, I have run into similar issues with the alignment of optics such as with image sensors.