How viable would it be to have both a Lotharingian-centric and Arletian-centric kingdom survive past the Middle Ages and into the modern era, at the very least into the 18th century? To be more concise, I'm asking for a timeline in which one state controls most of the Low Countries up to the French region of Lorraine and another controls Provence all the way to Savoy (whichever one the Burgundies fall under does not matter).
What would the effects of such state be on the history of Europe? How might they come about/survive?