The false Jesus described in the Qur'an is a muslim who was not the son of God, didn't die (at all, much less for everyone's sins) and will return to murder the remaining Christians and break the cross over their heads. The Qur'an says:

Christianity is wrong (sura 5:14);
Jesus is not the son of god (suras 19:35;  4:171);
Those who believe Jesus is God's son are accursed (9:30-35; 19:88-89; 37:151-152; 61:6);
Jesus was not crucified (4:157).

Further, Christianity teaches original sin, guilt, free-will choice and personal responsibility; while islam teaches (abuses its victims with) the exact opposite: that there was no original sin, and no free-will choice because allah is a slaver who is behind your every action, such that when, like Muhammad, you commit a crime, then if you got away with it, it was never a crime at all, since allah caused you to commit it and let you get away with it. But if you got caught, only then was a crime, because that was allah's will, too. Islam is a crime.