You'll need to fulfill the Messianic Expectations of Basically all 3; yet synchritize them somehow.
Having Miracle Worker and God are the same won't convince adherents to Islam, their idea of God makes it so its absurd and beneath God to assume anything that might limit any aspect of him- including taking a material body. None of the 3 believe He has a body; God is a immense primordial intelligence who thought the world into being. You'd almost need a 'John the Baptist' forerunner fortelling the immediate return of Jesus- who Muslims agree has a second coming. Jesus is a prophet in Islam and might be the only person who could convince them that 'X' version of God is the real deal. Jesus actually displays more miraculous power in the Quran than Muhammad himself.
This Jesus is also going to need to explain to Christians how they've deviated from the Truth, while still convincing them that they are still within the bounds of essential Truths if they put their faith in them. Will you keep the Trinity or not? If you do, then you may have a way to make this work well. comment (Jesus claims a kind of Divine Sonship and authority straight from the Father) Or maybe Jesus is the same Person as the Father- thus he is divine. [Christians say that the Son is the Logos, or Wisdom of God; where its almost like God's Self-Awareness is so real that it becomes a Seoncd personality, having the same nature and drawing on the same Power Source as the Father. The Holy Spirit is the Love of son & Father that becomes so real it has a Charatcre/Personality of its very Own). This returned 'Jesus' also must fulfill the Jew's expectations of their concept of Messiah, who will re-institute perfect sacrifices and fulfill all their sacrifices such that the only 'sacrifice' left is the Todah [Thanksgiving] Sacrifice of bread/grains.
The temple probably will need rebuilt; but you'll need to fulfill the expectation that God once again dwells in the Holy of Holies in the temple. If jesus were also God, and He performs a perfect sacrifice in the temple.. then there you go, God's presence is now once more within the Temple. He'll need to convince the Muslims that this is okeok to build over the Dome of the Rock. You could then Convince Christians that the Thanksgiving, (the Todah) sacrifice is the same Sacrifice of the Bread and Wine described in the Old Testament. The dead have to return to Life, as this is a tenant of both Islam and Christianity; possibly Judaism too. Jesus could say something like, 'As I transformed the Bread and Wine into my Body and Blood, now may the Body of Christ/The family of God once again be Transubstantiated back into flesh and Blood", thus fulfilling Christian understanding of the Last Supper, Apocalyptic expectations and also raises the dead by the same manner. Talk about a show of Power!
The most troublesome spot you're going to find is this: Is Christianity's idea of Divine Sonship and being co-heirs with Christ true? Or is Islam's Divine Slave-Master relationship true? part of Islamic Eschatology forecasts that Jesus will come to 'break the crosses', which they think means make War on Christians. Maybe you could turn this on its head by saying what was meant was that Jesus returns to break the crosses that we all carry- to give us an eternal rest (which is what the word Sabbath means) from sin and guilt . All three believe in a single God who has one people on Earth so if this 'Jesus' is going to succeed He must unite God's people- whether that's the Family of God or the Slaves of God.
God has to convince us and leave the Christian and Jewish understanding of free Will intact and let us decide, while displaying the power and Authority that God displays in the Quran.
Strange though it may seem, jesus or a man who can convince us he is Jesus, may be the only way to easily unite such diverse beliefs.