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