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