The original Fan Blade in my USB 100mm Fan was not very aerodynamic & noisy so when I saw R3Design's model I hacked it down about 50% to fit and also redid the fitment boss.
The result is quieter and without any testing appears to move the air better.
I printed with 0.15mm layers on a 0.4mm nozzle using PLA, I may redo at finer resolution with PETG at a later time.
Supports are required and you may need to tweak the top z contact distance (mine was set to 0.2mm)
There is also a 2nd print file of the hub boss if you want to do a quick print to see if it fits your fan.
The author remixed this model.