It’s worth noting that as commercial computer fluid flow modeling has gotten better and more accessible, there’s also been a huge demand to make quieter props/screws/fans from an area that isn’t so traditional.
Turns out that as electronics have proliferated, people have gotten more and more annoyed by cooling fan noise. Billions of dollars have gone into designing fans that are as close to silent as possible while still moving huge amounts of air. The experience and science behind that is readily available and can directly contribute to quieter in-water screws.
Here’s one example of a silent cooling fan, readily available on the market. Obviously moving air is a little different than moving water, but note the details of the fan - I selected a translucent unit so you could better see the blades. The strakes are not there for style.
https://www.amazon.com/Cougar-CFD12HBG-120mm-Cooling-Green/dp/B00DP5ZCS2?th=1
On noise: I'm certain some noise unnecessarily uses energy, thus an irritating inefficiency. Design of a quieter fan shape should save energy.
Ideally changing air molecule vibration to uni directional pulses and smoothing pulses toward a steady flow. Less noise, more airflow.
From 1980 to 1990 I was working with Automotive Radial Outflow Superchargers, and the impeller designs for them. I see some similar shapes in these cooling fans, even though they are axial.
It's true they are not designed for style, however they are things of beauty.
lotta vanes on the blades
i guess a Dyson fan is out of the question... 8^)