I can't really think of anything significant when it comes to Eitrigg's combat track record. Saurfang has mostly meme moments about cleaving things because Blizzard is oh, so funny and striking Malfurion from behind (which is of course bad, unlike sending an army of Rogues to scale the slopes of Mount Hyjal to strike a whole boatload of Night Elves from behind, which is the best thing ever). Grom got largely carried by his super Gronn-infused axe so in this case "an axe with an Orc" would be more appropriate. And Garrosh, prior to being gifted by a dead Old God (as well as after it) has amazing feats like defeating a guy he unknowingly poisoned, getting owned by Thrall the moment the latter started using magic or throwing a guy that wasn't even fighting him off a cliff.
Genn achieving his secret objective in his fight with Sylvanas says nothing about her actual combat prowess. In that fight she got hit straight in the face by the guy who was just recently killing Felguards with his bare hands and didn't even get a scratch while Genn ended the fight unconscious from poison, surviving only because both Sylvanas inside the temple as well as the Horde player waiting outside of it got paralyzed by plot convenience and let Genn's allies carry him out. And you're praising Malfurion here but he fled from Sylvanas at least three times during War of Thorns, even when Sylvanas was alone. Only for her to smash him into some trees, which was the only part of their final fight we've seen. And what exactly did Anduin counter in the cinematic?