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