Dynasty Warriors are pretty niche from what I'm gathered.
Isn't it something along the lines of Sengoku Basara?
A Zelda Musou is still a Musou with a different skin. Unless they change the game play significantly, I can't see people really enjoying this.
Basically yeah. But in certain respects it's more like the Gundam Musou games that are more about taking your favorite MSes and pilots and having them mow down wave after wave of cannon fodder along with the occasional general, who in Gundam Musou, would be a pilot and MS from the opposing side. Of course, the big thing is having fan favorites for players to choose from and so far that consists of Link and unhh... So right now, it's more about the speculation about which characters will they include, unless they take the Drakengard route and just make it Link alone with a massive arsenal of tools/weapons (and make the plot and characters batshit insane while having you assemble an armory of cursed weapons that'll doom you and those around you for shits and giggles; honestly, I doubt they'll go that far down the Drakengard route).
Which is the reason why I would've assumed that if Nintendo would Musou-fy a series, it would've been either Fire Emblem, Pokemon, or a general Nintendo Allstars (the former because it literally would've been a shoe-in, and the second might have made an interesting variation if they did something like have you play as a trainer until s/he releases a Pokemon then you get to play as the Poke protecting its master while trashing wave after wave of mooks and other trainers; and the latter being Smash Bros Musou).