Let's say that, in 1429, the English force the French to sign a peace in which the areas in orange below (those recognizing the Plantagenets as king), formed a separate Kingdom of France ruled in personal union with England. The War of the Roses would likely never have happened because England would never have lost its mainland territories and tensions would likely have never arisen (this would mean the Plantagenets might still be in power today). However, if the WotR did happen, it could've ended in a truce in which one line might have taken control of France, while the other would have stayed in Britain. Let's say the Yorks pushed the Lancastrians out of England, who in turn took control of France. As for Valois France, they would've been severely weakened, and a balkanized France would have greatly disrupted the European power balance. Louis XIV would not have been able to conquer territory from the HRE, and he would have likely directed his military aggression towards the Lancastrians instead, probably taking Gascony. The Lancastrians would also be far too weak to oppose the Holy Romans in any way, which would have changed the course of the Thirty Years' War, keeping Italy and Switzerland under German control for much longer, and delaying the collapse of the HRE. The Valois would have experienced the revolution at about the same time, possibly earlier due the monarchy having even less money, and Napoleon Bonaparte would have taken control as well, let's say. NB would likely have invaded and annexed the Plantagenet kingdom, but his advance into the rest of Europe would have not been as easy due to a stronger Germany and a smaller French army. Let's say he was content in annexing the Plantagenet, and thus would have avoided conflict with all the other European nations and stayed in power for much longer. As for Germany, they would have held on to the Low Countries, Austria, Switzerland, and northern Italy. These areas would have also been included in a united German Empire, which would mean Germany could easily have won the first World War due to lack of Italy as an enemy and much larger territorial holdings. The collapse of the Ottoman Empire would have been delayed as well, and perhaps the OE would still exist to the present day, or at least until the Arab Spring of 2011. A German-dominated Europe would mean WWII would never have occurred.
