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.
Save all Kissers of Wounds.
Provoke the meeting between Redento and Cleofás.
Cross the Bridge door in less than 3 hours.
Witness the last moments of Viridiana.
Unlock the ending A.
Get 100% of the game.
Get all rosary beads.
Beat all the arena challenges.
Get all sword hearts.
Use the Righteous Riposte 5 times.
Unlock the ending B.
Beat His Holiness Escribar.
Get all prayers.
Release all cherubs.
Buy all skills from the Mea Culpa shrines.
Achieve the maximum value of health.
Achieve the maximum value of flasks.
Achieve the maximum value of rosary bead slots.
Bring all the offerings to Lvdovico.
Get all collectibles.
Visit the tomb of The Lady of the Tailed Gown.
Achieve the maximum level of the Mea Culpa sword.
Talk with all the corpses.
Bring all the offerings to the Blessed Lord of Salty Shores.
Get all relics.
Help Cleofás in his path of redemption.
Achieve the maximum value of fervor.
Buy all the items of the Candelaria shops.
Help the Pilgrim reach his final destination.
Execute 5 different enemies.
Hatch the Egg of Altasgracias.
Discover all zones.
Beat Crisanta of the Anointed Blade.
Beat all types of enemies.
Beat Quirce, Returned by the Flames.
Beat Melquíades, The Exhumed Archbishop.
Beat Exposito, Scion of Abjuration.
Beat Esdras, of the Anointed Legion.
Beat the Our Lady of the Charred Visage.
Beat the Tres Angustias.
Kill 666 enemies.
Beat Perpetua.
Beat Ten Piedad.
Beat the Warden of the Silent Sorrow.