Good question. I don't know the European 9th gen well enough, but if I had to guess, I'd say lane departure warning.
The INT mode does operate as auto. However, the lowest two positions on the delay wheel do nothing when the rain sensor is connected (the wipers do not run). So I opted to get a stalk with the five "auto" positions.
By the way, I am wrong about the pink wire. Actually, on mine, "AUTO" is the default position when the stalk is disconnected (i.e. it doesn't have its own wire), so you should have it already.