While up against and facing opposite from thin walls with a two- or three-player totem, separate the totem via throwing or getting knocked back to clip the totemed players into the wall.
Since you have to be facing away from the wall, the momentum of the throw will immediately clip the player back in-bounds after clipping out. To get around this, press A to start the throw, then immediately move the circle pad toward the wall. This will throw and clip the player with forward momentum.
Totem Armos clipping allows for clipping through any wall that contains a Totem Armos in the stage.
Note: Totem Armos clipping is also possible while an enemy is riding the Armos, but it is precise.
The statues in stage 1 of 6-2 Stone Corridors work for clipping into the gate.