When I had the torqueedo on a Hobie PA, I made and tested some 3d printed props but never really got an all around advantage. It is easy to go faster and lose efficiency / battery life / total distance. When you transfer from flat clean water to a rough chop you really want the torque back in play.
I regularly cut real airplane props in my shop and have access to great FDA (fluid dynamics analysis ) software and it is easy to simulate new design effects, but when you print them and put on the same motor and battery you have rune the others on, there is always a trade-off in speed vs. duration/distance.
One of the props we are working on now for a flying car is on my single page website. www.dallascnc.com
We are about to cut the 5th generation of the prop in the next few weeks. The hub is designed so we can change blade profiles with little effort.
I have thought seriously about doing a live variable pitch prop like some of the older aircraft used. Adjust able for torque for acceleration or pushing against resistance or for speed once at cruise.