Warpshade
Usually lurks somewhere.
Now my knowledge of SOCs is less than complete, but if you designed the map with portals in mind, could you perhaps use the Tag changing action (Of which the real name I cannot remember) to temporarily create a linedef executor-teleport combo, which when given the correct flags, will maintain speed and alter the direction appropriately... It's probably not what you were looking for, but a step in a direction at least, right?