The IOM are looking to amend their ANO to incorporate ICAO Annex 6, which requires better regulation of GA through use of ops manuals, SMS, FRMS etc. If you are operating on the M- an amended ops manual should satisfy authorities outside of the EU, however if '[the OPRs] principle place of business' is within the EU then EASA have directed that they must - irrespective of registration - operate to the conditions of Air Operations Part-NCC, which are regarded as more prescriptive than the core ICAO Annex.
Where this is a little controversial is EASA are prescribing operating procedures to aircraft registered outside of their jurisdiction, and there is some discussion as to the legal basis. I am assuming (as I know little about FCL) that EASA has used the same bully boy tactics for licensing.
If anyone wants a steer on the rules, please PM