I know little about the Eberron setting, and can't bring myself to go grab any of my books at present, but I'll take a stab at it.
The beautiful daughter of a not too far away barbarian lord comes to the PCs for help (and to warn them of impending trouble for their own homelands). I'm envisoning these barbarians as a lot like vikings (perhaps they have even preyed upon the locale in which the PCs are in times past, but have been relatively peaceful during the reign of this girl's father). Her father has been ousted by a giant of a man bent on further conquest. Some of the old lord's men are now following the new conqueror, but some have remained faithful to their old lord and his daughter.
The PCs travel whichever direction to investigate the situation. Throw whatever you want at them on the road. As they near their destination some terrain/cold weather encounters would be great (if you stick with the viking vibe). Ultimately, the PCs will be taken into a camp loyal to the girl who set the adventure in motion. Rest, resupply, maybe engage in a challenge of strength or cunning to prove their worth. For some reason I see this groups as a little more civil than your typical barbarians, probably thanks to the calming effect of their female leader, sort of a cross between barbarians and fighters/knights (in my head I have been calling them the Knights of the Lily of the Valley).
From here the PCs make their way to the camp ruled by the new conqueror. Here they attempt to win support of some of the men away from him and quietly dispatch of those they can't win over. When battle comes, they find that the new conqueror is a magically disguised ogre born of a hag. I'm working on a hagborn template that will not be written up in time to do you any good, but you would be well served giving an ogre the improved grapple, rake, rend, damage resistance, spell resistance of an annis. It's up to you if he has his own spell like abilities or if his mother (and her covey) disguised him.
Options to continue the adventure...The ogre wears a large gemstone about his neck which is in reality a hagseye, allowing his mother and her "sisters" to keep watch on him. Perhaps teh PCs must now track down and defeat these hags.
The hags have a map in their lair which leads to the home of a dragon that they once served. Perhaps they offer this in parley, perhaps teh PCs take it as booty.