Designed to increase surface area like an old biplane, each blade has an overall “airplane style wing” but relieved and angled to possibly “compress” air vertices to orient correctly and exhaust them while and scavenging low pressure stall zones.
Did that sound good, lol?

(Frankly, I have no idea what I’m doing.)

Possible to print without support, maybe, but I used a tiny tree support in the center of each blade from the build plate just to help bridging.

Thank you to Major Hardware for peeking my interest and providing the hub design to go off of.
Here’s the link to the hub.
https://www.thingiverse.com/thing:4553248

If you haven’t seen it, Major Hardware’s fan showdown videos on YouTube are really good.