I've actually been thinking a lot about all four champions as low-effort DLC character conglomerates. I feel like the community will be up in arms if all four get a lot of dev time spent on them (it's okay for some series to have loads of representation with few games, but not Zelda evidently?), but each can use some animations for other characters as bases to be made. Semi-clones if you will...
Urbosa looks like she could take from Link easily, but she's more of a dancer and thus would be able to use some of Marth's or the Mii Swordsman's swordplay as well. Add to that Palutena's shield attacks and counter, and she'd work decently well. Specials could be a rising attack like Shulk's, a counter like Palutena's or Marth's, a lightning-version of Zelda's Din's Fire, and something like Pikachu's Thunder Burst with Ness's PSI Magnet visuals.
Revali could take a lot of his archery moves from Pit or Link, which would make for easy specials. Also, Falco could serve as a base for a lot of his normals. You've got Charizard's Fly for an up special, the Links' bows for neutral, just add bomb arrows to it (or even other arrow types), and a good side special could just be a charge like Palutena's Angelic Missile.
Daruk would need to borrow from the heavier characters, so he could take a lot from Bowser and DK (especially that rolling dash attack). Give him some stuff from Dedede and Ike for the swordplay, and he's good. Specials could be Zelda's Dins fire, Dedede's jump, Bowser's pound, and Ike's Unyielding Blade
Mipha's is the toughest since there aren't really spearmen in the cast, but she's not really a fighter anyway. She'd make a pretty good Palutena from all of those staff moves, and could adopt a few of Zelda's, Peach's, or Wii Fit Trainer's normals otherwise. Specials for her could be a healing down special like WFT's, Squirtle's Waterfall as an up special, an ice-themed Explosive Flame from Paly, and a neutral Paly's Heavenly Light retextured to look like rain, which does chip damage and heals Mipha.
It'd be tough to bring in one without the other three, so I think this would be great if they all took low dev time just to get all of them.
But what I really want....one more Hyrule Warriors DLC with these guys!