Hi Osten,
From the MMC Three Wheeler microsite specification page:
EU3 is homologated for UK, USA and Rest of the world
(ie not for Europe) EU4 is Homologated for UK and Europe.
https://www.morgan-motor.co.uk/wp-content/uploads/2018/10/M3W-110-Years-Price-Lists-Low-Res.pdfI know of people who have tried to buy a 2018/9 new M3W for registration in Europe and been advised by MMC, via a main dealer, that this is not possible.MMC were slighlty vague on the cutoff date but anything newer than mid 2017 will need to be EU4 without any appearance pack.
However, a UK registered EU3 or EU4 with EU3 apperance pack can continue to be used in Europe and maybe that is where the confusion is .
I know you've been on a long journey ot fiond your M3W but please make sure that MMC are absolutely clear in a letter (not an email) that the car they supply to you will come witl ALL neccesary documents and approvals to allow it to be regiseted in Mainland Europe.