Unfortunately, it's impossible to project modern hegemonic/multipolar (depending on who you ask) worldview onto political actors in pre-modern Europe. But we can certainly examine the power relationships between the Ottonian Emperors and the other political actors in Europe.

So let's clear something up: I'm an Ottonian fanboy, so this answer will actually dip a lot into the 10th century. Otto I was an astounding person; his father Henry even more so; the first person to be proclaimed King of East Francia who was not an ethnic Frank, and (more or less) invented the Germanic model of "Elective Monarchy" with the Kaiser as a Primus Inter Pares in order to justify his ascension. From their base of power in Saxony, the Ottonians lay the foundation of what would become Germany, the Holy Roman Empire, and influence events in Western Europe for years to come. So the Ottonian Emperors of the tenth and eleventh century were definetely a force to be reckoned with. In the text below, I'm going to refer to Henry I, Otto I, Otto II, Otto II, and Henry II as "The Ottonians," which doesn't rally do justice to the individual successes and failures of each ruler, but it certainly very convenient for our purposes.

So what was going on outside of the Kaiserreich? To evaluate if the Ottonian empire was a true hegemon, we have to examine what was going on across the Rhine in West Francia. And what is certain is that the ascension of a Saxon in East Francia definetely strained ties between East and West. The Carolingian notion of submission to a single Emperor was still alive and well in the legal scholarship of the era, however the stark cultural, linguistic, and diplomatic differences between East and West Francia had by the late 10th century progressed beyond reconciliation. In fact, opposition to East Frankish authority on previously West Frankish territory acquired through inheritance or alliances was one of the few pretexts the last Carolingian kings in the west could use to rally their subordinates for a common cause. So a good analogy for the differences between early France and early Germany is that the Germans had pretty much hit a "Reset" button; ending up with the strongest dynasty in Germany holding the top job, but nonetheless were toeing a fine line with their subjects such that the realm didn't devolve into a free-for all. On the other hand, the French were dealing with a declining monarchy, which only really exercised direct rule in the eastern portion of France; well positioned to affirm themselves on the border with their eastern neighbors and little else.

So, as you can imagine, that's our first key difference between later hegemons and the Ottonian Empire. Although the Ottonians certainly had the legal and moral authority (according to the norms of the time) to impose themselves on their western neighbor, in practice they were limited to marginal interventions in border territories Lorraine and Flanders. But this isn't to say they were unsuccessful rulers, quite the opposite: in fact, the Ottonians were able to set up an early bureaucracy through the clergy, undermining the landed nobility and creating the most efficiently run monarchy in Europe at the time. And because the clergy/administration was based in cities, their expanded authority and independence was particularly beneficial for urban growth economic prosperity, creating even more resources available to the Ottonians, allowing them to dominate the Slavic tribes living on their eastern border, subjugate Bohemia, and soundly defeat attempted rebellions.

But it's fair to say that, unlike more modern hegemons, the Ottonian empire could not project power far beyond its immediate border. Relations with the Byzantine Empire, although warm, remained diplomatic. The subjugation of West Francia, although certainly an aspiration, was only feasible via a protracted conflict that would almost certainly unite the French nobility against the halfhearted participation by the German Princes. And if dissatisfaction grew enough, the lesser German rulers could remove the Ottonians from their kingship just as easily as they had elevated them; a wholesale invasion of West Francia was off the table.

There is, however, an achievement that places the Ottonian empire one whole tier above the contemporary Byzantine empire and France that goes well beyond having a more efficient bureaucracy. That achievement is the conquest of Italy, the third Carolingian successor kingdom.

Even prior to the extinction of the Carolingian dynasty in East Francia, in Italy the last Carolingian ruler had died heirless in the first half of the tenth century. This had led to a brief union of the crown of Italy with Burgundy (a rump Kingdom formed out of the original third Carolingian partition known as "Middle Francia") with the final outcome seeing the overextended Burgundians losing Italy while their kingdom slipped into irrelevance. The Marquis of Friuli, Berengar, defeated the Burgundians and was proclaimed King, but under unclear circumstances the Kaiser Otto I came to the conclusion that Berengar wasn't as warmly supported as it seemed. After a number of diplomatic and military stalemates which saw important supporters flip flop back and forth, Otto was able to establish a sort of client-state relationship with Berengar, until Berengar's conflicts with the Papacy and clergy (both of which were central in the administration of the Ottonians in Germany) pushed Otto to descend into Italy, depose Berengar by force of arms, and crown himself King of Italy with surprisingly little opposition on behalf of the Italians.

Sure, Italy had been seeped in feudal anarchy for nearly a century by the time Otto arrived with his army. However, Italy's immediate neighbors, the Burgundians and the Byzantines, had proven unable affirm themselves on the peninsula. Only the Ottonian administrative/political machine could bring some semblance of order in Italy. That's not to say they were completely successful: only in Germany the monarchy had succeeded in placing itself one step above the clergy, very clearly relegating to a subservient role. Because the Ottonians were a German speaking and Germanicentric dynasty, by empowering urban bishops in Italy they didn't have easy lines of communications with, the situation in Italy quickly devolved into fierce inter-uban competition between local political structures that could only be placated by personal visits by the emperor.

So in brief, the Ottonian empire was a remarkable entity for its time. The Emperors were in control of the military, the administration, and the clergy; an authoritarian's dream! However, the Emperors also had to be careful constantly appease their powerful vassals, which made for difficult power projection in the style of modern hegemons. Still, they weren't actively running from their subordinates as was the case in France, and the one major military expedition against an equivalent power was won largely through paperwork, itself a remarkable (if curious) achievement.