Dovahkiin actually seems pretty low on the list, unfortunately.
The most requested/likely Western 3rd parties I see around are:
- Rayman (Ubisoft), based on the random trophy he got in the last game
- Banjo-Kazooie (Formerly Rare, now Microsoft), since they were big names in the N64 era around the time of DK64, which went away once Rare got bought out
- Steve (Minecraft, now Microsoft) for being a worldwide phenomenon. For me, though, I'd see a stage much more likely than the PC since the game is all about what you can make
- Shovel Knight and Shantae (Indie)
I think Dovahkiin also gets hurt a bit since requests for him didn't really crop up until after the Skyrim port was announced, which was WAY after the ballot. Honestly the two Bethesda guys and Solaire are all suffereing from this while the others aren't
Still, Smash has never had a western 3rd party character. Sakurai likes to have creative control but be accurate to the character, so there may be a lot of language barriers in addition to legal barriers. Add to that that a lot of these characters are "Hello, [INSERT NAME HERE]" player characters, and things are not good for most of them outside of BK and Rayman.
I think Dovahkiin's best chances would be if Skyrim really impressed Sakurai and the Japanese. Breath of the Wild definitely did feel like a Bethesda-esque RPG, and they definitely did talk to each other to put some Zelda stuff in the Skyrim port. The Shouts would make for a really fun playstyle, but with few requests...it's not looking good. I can still dream though.
Alduin would make a great boss. I dunno if we'll be getting SSE back, but I think a new Smash Run is logical, and I'd love to see the Draugr in there. They look so good in Skyrim, and they're pretty iconic enemies in their own right.