Is it possible that such a one would pray to Mary and the saints? Yes, it’s possible. But it is also an act of idolatry, implies that God is less compassionate than Mary, and has zero biblical warrant. But just as there are Presbyterians who don’t believe what Presbyterianism teaches about salvation, so there are Catholic and Orthodox people who don’t believe what their church teaches about salvation. They are resting in Christ, and are sadly misguided in practices such as praying to Mary and the saints.
If that is you, I suggest you have a moral obligation to leave those churches, particularly the Roman Catholic Church, which is unashamed in its denial of the biblical gospel as plainly stated in Ephesians 2:8-9, “For by grace are ye saved through faith; and that not of yourselves: it is the gift of God: Not of works, lest any man should boast.”