In Kali Yuga, Vishnu has incarnated as Buddha and Chaitanya Mahaprabhu. Also, his Kalki Avatara is not yet to appear.
Like him, Is any other deities incarnate during Kali Yuga and also yet to appear? Is any scriptures mention that?
Lord Ganesha will appear as avatar and also destroy the sinners by riding on a blue horse and the new age of Satyug will begin. This incarnation of Ganesha is described in detail in Ganesh Purana. In this Purana, Lord Shiva has told Parvati that at the end of Kalyuga, Lord Ganesha will incarnate with Charbhuja.
In this incarnation, the name of Ganesha will be Dhurvarna and Shurpakarna. God will have a pillar in his hands. By his will Ganesha will generate army and weapons. Ganapati's eyes will be filled with anger due to the increasing morale of sinners and loss of religion. To destroy the sinners, Shurpakarna will rain fire with his eyes.
After destroying the sinners, when the anger of Ganesh ji will calm down, then Lord Ganesha will bless the saints who are hidden in the mountain shrines due to the fear of the wrongdoers and will entrust the restoration of religion in their hands. In this way, Satyuga will start from the hands of Ganesha again.