Here is the full list of all 45 Blasphemous achievements. It takes around 25-30 hours to unlock all of the achievements on Windows.
Get all rosary beads.
Get all prayers.
Get all relics.
Use the Righteous Riposte 5 times.
Bring all the offerings to Lvdovico.
Help Cleofás in his path of redemption.
Help the Pilgrim reach his final destination.
Bring all the offerings to the Blessed Lord of Salty Shores.
Buy all skills from the Mea Culpa shrines.
Beat all bosses without flask consumption.
Get 100% of the game.
Get all collectibles.
Achieve the maximum value of flasks.
Achieve the maximum value of rosary bead slots.
Visit the tomb of The Lady of the Tailed Gown.
Unlock the ending A.
Release all cherubs.
Talk with all the corpses.
Achieve the maximum level of the Mea Culpa sword.
Cross the Bridge door in less than 3 hours.
Beat all the arena challenges.
Get all sword hearts.
Save all Kissers of Wounds.
Achieve the maximum value of fervor.
Provoke the meeting between Redento and Cleofás.
Unlock the ending B.
Beat His Holiness Escribar.
Discover all zones.
Beat Crisanta of the Anointed Blade.
Beat all types of enemies.
Achieve the maximum value of health.
Beat Quirce, Returned by the Flames.
Hatch the Egg of Altasgracias.
Beat Exposito, Scion of Abjuration.
Buy all the items of the Candelaria shops.
Beat Melquíades, The Exhumed Archbishop.
Beat Esdras, of the Anointed Legion.
Execute 5 different enemies.
Witness the last moments of Viridiana.
Beat Ten Piedad.
Beat the Tres Angustias.
Kill 666 enemies.
Beat the Our Lady of the Charred Visage.
Beat Perpetua.
Beat the Warden of the Silent Sorrow.