Mistborn:
Vin: Slytherin, for sure!
Kelsier: also Slytherin
Elend: I would say Ravenclaw, but in the 3rd book he is definitely acting more like a Gryffindor and his strong values kind of fall in Huffelpuff territory
Breeze: Slytherin, I never realized how many Slytherins there were in this book franchise
Ham: Getting Huffelpuff vibes of him, but Gryffindor fits too
Sazed: Ravenclaw, but I get why people also say Huffelpuff
Spook: I guess Gryffindor, but not really sure with him
Mistborn Era 2:
Wax: Gryffindor
Wayne: Weird Slytherin/Hufflepuff mix
Marasi: Ravenclaw
Steris: I think Slytherin (she is really resourceful and clever, also quite ambitious and determined)
Marsh: Ravenclaw I guess, not sure with him
Elantris:
Raodan: He could be almost anything, but I guess I would pick Ravenclaw for him!
Hrathen: definitely Slytherin, no doubt
Sarene: another Slytherin (funny I always sure with the Slytherins)
Galladon: I'd say Huffelpuff, he isn't bold enough to be a Gryffindor and not as eager for knowledge as Ravenclaws, but he is definitely loyal and hard working
Way of Kings (just read part 1):
Kaladin: Gryffindor
Shallan: I guess Slytherin does kind of fit even thoug she is smart, she isn't smart enough for me to be a Ravenclaw
Dalinar: Gryffindor, but he is evolving into a Hufflepuff
Adolin: Another Gryffindor
Renarin: Ravenclaw
Jasnah: A Ravenclaw at its finest
Sadeas: Slytherin
Elhokar: I dont see him anywhere, he surely as hell isn't Gryffindor or Ravenclaw or Hufflepuff... not sure if he is clever enough to be Slytherin, I think not...
Rock: seems like a Hufflepuff to me
Szeth: Weird choice probably, but Hufflepuff. He could be Ravenclaw, but I don't know enough yet to judge him properly
I have yet to read Warbreaker, so I will be back in a few month probably to edit that in, now I am thoroughly busy with the Way Of Kings series since I only just read Part 1, so i still have 4 books to go and Oathbreaker isn't broken into two books so that will take long enough. I should also study instead of reading these amazing books, but Brandon Sanderson books just can't wait!! I also read the Reckoners series but since it isn't Cosmere related I won't sort them into houses