Deciding what to ship and what to sell happens weeks before departure, while the removal quote is still being priced by volume. Americans face the sharpest version of it, and the airport plug adapter that seems to settle the question turns out to answer only part of it.
Depends entirely on what's inside the appliance. The Netherlands runs 230V/50Hz single-phase power against the US standard of 120V/60Hz, which is a real difference, not just a plug shape issue. Anything with a "dual voltage" or "100-240V" rating printed on its charger or nameplate — laptops, phone chargers, most modern electronics, many camera and audio devices — will work here with nothing more than a cheap plug adapter, since the internal power supply already handles the voltage range. The problem is anything with a motor, a heating element, or a mechanism timed to the electrical frequency: hairdryers, kettles, toasters, space heaters, older clocks, and many kitchen appliances either won't reach proper temperature, will run at the wrong speed, or will simply burn out on 230V. A step-down transformer can technically fix the voltage mismatch but rarely the frequency one, and by the time you've bought a transformer heavy-duty enough for a kettle or hairdryer, you've usually spent more than a new Dutch one costs. Practical rule: bring the electronics, sell or donate the heating and motor appliances, and buy replacements locally once you're here.