In general:
-Unclear numbers. "Raises your party members' attack power." By how much, dog????? Be clear, ffs!
-Damned stuck in a nearly invisible, but unwalkable terrain when walking around the map.
-Unskippable tutorial and intro/cutscene.
-Voice actingn't. Like, when the voice actors sound like they're not paid enough (because they probably don't).
-Bullet sponge enemies.
-Head-bobbing.
-Chromatic aberration.
-Completely uncontrollable AI allies.
-Good sequel, bad 1st game, but the story is directly related.
In RPG and games w/ RPG mechanics:
-Suikoden.
-When you have to kill off your units to recruit special unit.
-Wack economy. "Ah, yes! The famed legendary mythical dragon slaying sword! I'll take it off of you for 2500. Oh, this masterwork steel mace? 10000, take it or leave it."
-Fights so ez, consumables are basically collectibles, and buff/debuff skills are UI noise.
-Social/dating sim elements. Yeah, like in Persona 3 onwards. I hate it.
-Rescue or Bodyguard mission.
-No quest journal.
-Can only take one sidequest at a time.
-Sepiroth.
In Horror:
-Cheap jumpscare (both visual and auditory)
-Advanced Darkness™, when flashlight doesn't illuminate the surroundings enough.
In games of all genre where choice matters:
-UNCLEAR DIALOGUE CHOICES THAT CAN EASILY BE MISINTERPRETED (I'M SEEING YOU THERE, S.T.A.L.K.E.R. 2, DON'T YOU FCKING HIDE!!!!!)
-Giving no choice to do something better. Like only "shoot or knock out," instead of "shoot, beat the crap out of him and rob him dry for selling me out and throwing a kettle at my face, interrogate for more information, or knock out." (Stay still, Stalker 2, it's still you.)