Here in the US, the FAA want nothing to do with them "Ground Effect Vehicles".
It has become a US Coast Guard issue and the licence required to drive the things are the same one as for operating a boat for hire:
The lowest commercial boat ticket is called a "Six-Pack" Licence as ya can carry six pax.
To obtain that ticket, 360 days of sea-time is required. (Each day must be at least 4 hours on the water.)
Then a course and a written test for the Coast Guard. (Not easy)
A company here in the US is developing a similar, but smaller Ground Effect Vehicle, but were set back last year when they crashed the prototype.
The pilot/skipper barely survived, but is okay now.