They had been accused by authorities of adopting the ideology of Islamic State and travelling abroad for training.
According to the Reuters news agency, lawyers representing the group gave no immediate comment.
It is alleged the group also intended to attack a shop selling alcohol in the coastal city of Damietta.
Life sentences (25 years) were handed to 18 of the men during a court hearing convened in the capital, Cairo. Eight received 15-year sentences, while four were jailed for ten years.
Previous plots to attack churches in Egypt had proven successful - with deadly effect.
Twin suicide bomb blasts targeting Coptic churches in Alexandra and Tanta left at least 45 people dead and 126 others injured on Palm Sunday in 2017. Islamic State claimed responsibility.
Twenty-five people were killed in an explosion at a chapel near the Coptic Orthodox Cathedral of St Mark in Cairo on 11th December 2016.
Seventeen people were sentenced last October to death over their involvement in the three blasts. But Amnesty International condemned the legal proceedings as an "unfair military trial".
Since President Abdel Fattah al-Sisi came to power following a military overthrow of the Muslim Brotherhood in 2013, efforts to crack down on Islamic extremists have been stepped up by authorities.
Christians - who compromise approximately ten per cent of Egypt's population - and tourists have been particular targets in attacks.
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