I'll finish watching the video later.
Back in 2007 I did some research on the topic, sadly most of the links have vanished - never happened back when we had books, we just had to return them to the library.
A Whale of an Idea
https://www.boatdesign.net/threads/a...an-idea.17382/
PDF link from that thread that includes Mr. Fish (
Dr. Fish?):
https://www.boatdesign.net/threads/a...an-idea.17382/
There was an orange colored hovercraft fan blade (w/tubercles for noise reduction) that was supposed to hit the market back then, it never materialized.
EDIT:
Article on modifying a standard airfoil.
https://www.researchgate.net/figure/...fig1_236679345
Seems to be a related video on this: