https://drivenintodarkness.itch.io/one-page-monster-cheat-sheet

Use this monster cheat sheet to create a complete set of foes for encounters and dungeons in any game system. Keep the players as the focus don't worry too much about the core stats of the opponent in your game or during prep, the stats of any given monster in a monster book are largely the same scaling with level, while the thing that truly distinguishes monsters from one another is special abilities they have that surprise the players, not the fact that they had 12 as opposed to 16 health.