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