In Pokemon 5th gen, can Swift Swim still be legal if you don't have a Drizzle pkmn, or vice versa?

The Drizzle/Swift Swim combo is only banned on Smogon. But if you are playing by their rules, then a Rain Dance/Swift Swim combo would be fine. No other weather based ban has been implemented. There was a recent vote on Sand Veil being banned, but there was no majority decision, so it is still allowed.