France and a unified, centralized HRE would constantly be at odds with each other and could end up in a situation where their rivalry defines the Middle Ages, as opposed to that of France and England. Their interests almost always run counter to each other.
It would be difficult to predict if a version of Protestantism even arises, let alone when. The circumstances that could lead to a unified German HRE could butterfly everything away if the POD is early enough. However, there were always religious "heresies" cropping up throughout the Middle Ages, any one of them, depending on the circumstances, could have had the impact that Protestantism did in OTL. In the scenario I proposed earlier, the Great Schism between Catholic and Orthodox hadn't occurred yet, though the churches we're drifting further apart by this point and it could be argued that an eventual schism could be inevitable. However, Otto did arrange for his son, Otto II, to marry a Byzantine/Roman princess to mend relations, so with the right circumstances and decisions, a Great Schism could be delayed or outright averted.