If you want a Physical passer go with
Ninjask
Nature: Jolly or Adamant
EVs: 252 Def, 252 Sp. Def, 4HP
Item: leftovers
Swords dance
substitute
x-scissor
baton pass
If you want a special passer go with
Masquerain
Nature: Modest or Timid
EVs: 252 Speed, 126 Def/Sp.Def, and 4HP
Item:???
Quiver dance
substitute
Baton pass
bug buzz
I use ninjask as a passer, usually sending him in after setting up light screen and reflect, he is fantastic. Don't go with DW abilitys, their normal ones will work better.