I have also seen a technique, albeit from a BJJ instructor, where you put your shin and sort of... "leverage" your opponent to turn their head. I'll post the link down below, but I wondered if this is illegal also. Any help would be appreciated. I don't want to practice anything that won't be legal in a match.
Here is the link to the video. He does the technique the "nice" way first, and uses his knee at about the 2 minute mark. In the video, he uses his hand to push the face away, which is obviously illegal in judo, but I wondered if the knee on chin aspect was.