Questions about breeding Pokemon? (Solosis)

Q:#1 So I'm trying to get a shiny Solosis using the Masuda Method. I'm pretty sure nature effects it's stats, but I'm not sure.

Q:#2 Also, it has two abilities- Overcoat and Magic Coat. I'm pretty sure Magic Coat is better. Is it?

Q:#3 Is there an item that passes down abilities like the everstone passes down nature? Thanks!