I'll cover Church Fathers (eg, St Jerome, St Augustine, St John Chrysostome) and St Robert Bellarmine, and more:
Did Archbishop Carlo Maria Viganò say Pope Francis is Antichrist?
Can Pope be the Antichrist?
Some are accusing Archbishop Viganò of saying that Pope Francis IS the Antichrist. They also wrongly assume that Archbishop Vigano denies the indefectibility of the Apostolic See of Rome.
This is based on his use of the adjective "antichristic" in his recent declaration regarding the Vatican Health Conference when he refers to the "Antichristic counter magisterium."