Is there any Koranic verse that states that God has vested the knowledge and authority of everything in the manifest Imam. If so, who is that manifest Imam in our time?
This is referring to Qur'an 36:12 and there is some discussion here:
https://www.al-islam.org/ask/what-is-the-full-significance-and-historica...
If the phrase "imam mubeen" is understood to refer to a human Imam, such as Imam 'Ali, there is no reason why it has to refer to a human Imam who is presently living since the souls of humans exist after death, and the Qur'an states that martyrs are alive. Although, of course, it could, and God knows best.