All prospective pilots, whether they want to fly aeroplanes, gliders, helicopters or balloons, have to undergo clearly defined training. This includes theory lessons as well as practical training in the type of aircraft concerned. All training courses have to be concluded with an examination.
How hard is it to fly in Switzerland with FAA certificates?
Anyone have experience with "Validation of a foreign license" which is good for 1 year or "Conversion of a BASA FAA licence to EASA Part-FCL PPL Licence"
As long as you find an N-Number (US registered) aircraft in Switzerland, then you don't need to bother with any Swiss pilot license regulations. You can just fly them with your US certificate.