No! ...are you insane?
Unless you want to catch another Rayquaza in R/S/E by going through nearly the whole game, migrate it with an obscure DS earlier than the DSi Model to a Gen4 game, transfer it to a Gen5 game and use PokeBank to get it to Gen6, then no. That trade is not worth it.
You can get Misdreavus in Generation 5 (only White, however) in the Abundant Shrine.
You can get Misdreavus in Pokemon Pearl in the Eterna Forest and Lost Tower (Night).
You can also get Misdreavus in Pokemon HG/SS from Mt. Silver, The Cliff Cave, or in the Forest Safari Zone.