The French government as recognized by the allies and later United Nations never recognized the occupation of France as an annexation.

A better example would be Alsace Lorraine (now Alsace moselle), which was legally part of the German Empire from 1871 to 1918.

Countries and their territories are not immutable, and historical governments of countries have no obligation to follow modern notions of historical preservation. Anything held for long enough is a historical artefact. There was no government of Greeks by Greeks from 1453 until the Russian/ottoman capture of the ionian islands in 1800, and Greece itself wasn't a country until either 1821 or 1830 depending on when you want to say it's recognized.