There is no acceptance of the IMC rating abroad in the sense that I think you mean, Fuji Abound.
The Germans have a CVFR rating (or at least used to) which is required for a German PPL for VFR flight in Class C airspace. It used to be the case that the German authorities accepted, informally at least, that an IMC rated pilot would be allowed to fly VFR in class C. I've also heard reports that the German authorities do not require any rating for a pilot with a foreign PPL to fly VFR in class C.
For IFR flight in France or Germany (or anywhere outside the UK) you need an Instrument Rating.