À UK Class 2 Medical allowed me to fly EASA registered aircraft here in France before 1st January 2021, I don’t know if that will apply today. Obtaining a Class 2 with a French AME is not a problem, even with an ECG it’s a lot cheaper in France. My lifetime UK FCL PPL SEP is not valid in France to fly EASA Registered aircraft even though the license is current and re-validated.