The EVs would be 252 SpA, 252 HP and 4 SpD
All EVs upon fusing are based from Kyurem - so you could have 4 HP/252 Atk/ 252 Spe Kyurem and a Reshiram with like 100HP/100Atk etc. (you get the idea) and Kyurem's stats would be used. Additionally, the nature is taken from Kyurem as well.
I'm not sure about the moveset, it might stay the same as Kyurem's or get a new one. Probably the former :P
Anyway hoped I helped!