Here are four videos created by Youtubers that show the changing borders in France during the Middle Ages.
The Youtube channel Geography and Space created this video showing the various borders of states in what is now called France, between the years 418 and 2018. This includes the Kingdom of the Franks, the Kingdom of West Francia, and the Kingdom of France, as well as English possessions in France during the Middle Ages.
Danzig HD Mapper created this map that shows the domains of the King of France between the years 957 and 2018. It is notable in that we only see the territories directly or indirectly ruled by the French kings, which during much of the medieval period were considerably smaller than what is recognized as France today.
Khey Pard created this video that shows the history of France from 481 until today’s French Republic. This includes detailing various divisions during the Merovingian period and the territories of the Anglo-Norman Empire.
The final video, by EmperorTigerstar, shows the changing borders of France and England during the Hundred Years War, divided by every month (although some periods are skipped over).