Spalk
Iruka said he can’t hand out the academy jutsus without Sasuke demonstrating 4 years’ worth of academic knowledge… Meanwhile, Kakashi was using those jutsus when he was 5 years old and they were demonstrating those jutsus in his first and only year in the academy.
Hello. You forget that Kakashi had White fang to teach him. Sasuke also learned the fireball jutsu from his family and could also learn the academy 3 from them if they weren't dead. However the academy has to follow a protocol and can't just go around teaching jutsu because most of the kids are not mature enough and a large number of them are from a civilian background.
Transformation jutsu is not just illusion. Naruto used transformation to make him and gamabunta kurama, they haved claws and fangs to catch shukaku. Naruto few times transformated into big suriken , his clones and saske throwed him like suriken and he was flying like suriken. Saske know it's Naruto because of weight.