If he wants to live here so much, then tell him to return home and apply as a skilled worker. Don't try to cheat the system.
And no, there won't be legal implications for you, but you should really tell your brother about the downsides of living illegally. No social insurance number, therefore he will have hard time finding a good paying job, or any job for that matter, as companies who hire illegals face stiff penalties. Since illegals risk deportation, they are sometimes subject to blackmail or paid very poorly. When he gets sick or injured, he will not be covered. He will not be able to get a driver's license or a bank card.
And finally, if he decides to try driving by himself and gets pulled over by police, it's pretty much game over for him, as he will be caught and deported. Same applies if he ever gets in trouble with the law, or if someone discovers he's an illegal and reports him.