Foreign registered Annex II microlights are allowed in NL in accordance with
wetten.nl - Wet- en regelgeving - Regeling MLA?s, MLH?s en schermvliegtuigen - BWBR0015237
The relative bit > or < reads:
MLA, MLH and powered parachutes, registered in a European Civil Aviation Conference (ECAC) country and which do not have a Certificate of Airworthiness (CofA) as prescribed in ICAO annex 8, are given a general permission to use the airspace of the Netherlands (FIR Amsterdam) under certain conditions on a temporary basis.
The conditions are the following:
1. The Civil Aviation Authority of the country of registry has issued a non ICAO CofA, a permit to fly, or any other document permitting the operation of the aircraft;
2. The operating conditions and limitations set by Civil Aviation Authority of the country of registry are applicable whilst operating in the airspace of the Netherlands.
Foreign registered homebuilts are allowed in accordance with AIC 16/O2.
Integrated Aeronautical Information Package the Netherlands