i have a stat up pokemon use a Ninjask with
baton pass, sword dance, and double team, and protect also the abitily speed boost
or a yanmega i am not sure if they can learn baton pass
or yanma/ yanmega if it learns baton pass naturally but it has speed boost as an ability
how to use them
use the pokemon in a double battle
because this tactic is awesome.
first use ninjask/yanmega use a stat up move
make the other pokemon use the move "follow me" make sure it a tank pokemon, (have leftovers)
that way it gets the damaged for ninjask/yanmega while its stats get raised.
after you should get a speed boost then switch.
i always do this when using slow pokemon like Tyranitar and Metagross.