I do not have e-foil, I only deal with the research and development of new propellers. Current commercial propellers are completely unsuitable for e-foil. They are very cheap but have a very low efficiency of 15-20%. Such low efficiency does not make it possible to use the power of a very expensive battery and engine to have e-foil a high stroke and a long voyage. E-foil is a very special watercraft that needs a specially optimized propeller. Such a propeller can not be bought anywhere, it has to be designed by a hydrodynamics expert.
That’s why I’m willing to design a propeller for e-foil, but it’s got to be the best fully functional prototype of direct drive. The best direct drive should include an outrunner motor, one axial bearing (instead of the original radial bearing), one watertight seal and a special aluminum case (can not be bought, must be produced on a lathe) in which the engine is fully inserted. This creates a compact rotating unit that does not reach the water through the seal, and it is enough to attach the propeller. The motor shaft serves to be attached to the front fixed section of the hydrofoil leg. I think this solution is the only one for e-foil - it does not reduce the motor torque, it will provide sufficient cooling and easy maintenance (gasket replacement). For this compact rotary unit it is very easy to design a highly efficient propeller.
Perhaps someone finds and my concept of direct drive is modeled in 3D CAD. It is very easy. But there must be a way to get three wires from the engine from a rotating rotating unit. There are two solutions, one is very cheap, but a bit laborious, the other is more sophisticated, but more expensive. I would have modeled this concept of direct drive, but I would prefer to just model the propeller. The prototype of such a direct drive concept is inexpensive, easy to manufacture. If an optimized propeller is connected to it, it will become the best propulsion for the hydrofoil in the world.
I do not think this is a good topic for further discussion.