These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Fatal Frame
Accidental Innuendo: A ghost in Crimson Butterfly died in the lost village while looking for her boyfriend ( by being strangled by his ghost, actually). One of her diary entries has a single page stating simply "He came" and, even better, she utters a haunting "you finally...came" when defeated. Considering how hard this phrase would be to work around, the translators probably realized the implication and just plowed on ahead.
Fan Dumb: Plenty with regards to Deep Crimson Butterfly, from the "purists" who refuse to buy it because it's a remake, to the people upset with the change in voice actors. There are even some who refused to buy the remake on account of the change in the ending theme.
It Was His Sled: Mio will kill Mayu. This was originally the big plot twist in Fatal Frame II: Mio thought Mayu would kill her until she read the notes that said the twin that came out second was the eldest (it was thought that the "elder" twin would let the "younger" twin be born first).
Les Yay: Miku and Rei gave off mild vibes in the third game.
"Having trouble sleeping? Do you need to sleep in here with me?"
Miya and Misaki also have a few moments which are... questionable.
Narm: Protip: if you're going to try to make headless ghosts scary, do not make them constantly repeat "Where's my head?", especially when their head is on their shoulders for 80% of the fight. And Female Head rolls in midair as she moves, which just makes her hilarious.
Scrappy Mechanic: The Stealth-Based Mission in III; while there is precedent for being stripped of your camera, III takes the cake by forcing a character on the player whose ability to squat behind things is advertised as his 'special ability'. Made even worse by it not working most of the time.
From the same game, the frickin' candles. After a certain part of the game, the whole house becomes covered in miasma, causing more and more dangerous ghosts than usual to appear, including Reika who is unkillable and kills you in one hit even if you have a Stone Mirror. Also, the whole game turns black and white, making it hard to see anything. The only way to counter this is to find candles, but they last a few minutes at best, are scattered at inconvenient locations in the manor, so you have to go out of your way to find them. In the end, you're stuck between a rock and a hard place: Do you hunt for the next candle (being hunted yourself by Reika on the way) in order to be able to proceed more safely to the next location you actually need to be, or do you just try to rush on without and risk getting one-shotted somewhere close to your goal. Good luck trying to kill those required ghosts with an unkillable one-hit-kill distraction chasing you around!
Permanently distorting the player's view and forcing him to run as fast as possible without paying attention to his surroundings in a game which in no small part relies on its visual aesthetics? I see nothing wrong with this plan...
In IV, the piano segments. They require you to point at the narrow keyboard keys with game tending to think you hit the ones next to them instead, and they're also picky about timing. To make things worse, if you fail three times at the end of the final boss fight, you have to fight Sakuya again and repeat the process.
Squick: The shots of Mayu after her fall when she was a kid, in II and its remake. It's no wonder that she's still walking with a limp all these years later.
Reika as the final boss in III. Whilst Kirie and the Kusabi from I and II had One-Hit Kill moves, they were both fairly manageable bosses thanks to their slow speed and easily read movement. Reika, on the other hand, has a habit of frequently flying high in the air, which on its own makes her rather hard to pinpoint without going into the movement limiting finder vision, so good luck getting out of her way when she comes dive bombing towards you straight afterwards. On top of that her own one hit kill attack involves appearing in a completely unpredictable position close to you. If you're not facing clear away from her when she appears, you won't be able to avoid running smack in to her and she will gladly watch that health bar of yours go all the way down whilst groping your lifeless corpse.
The fight with the Utsuwa (dancer) and Kanades (accompanists) in the fourth game also ranks high in terms of sheer frustration. The Kanades, par for the course for child ghosts, are Goddamned Bats that work as a team, with one or more serving as decoys while another (most likely directly behind you) goes in for the kill. There are also five of them. Meanwhile, the Utsuwa is a wild card, teleporting and attacking more or less at random. If you haven't mastered the evade function prepare to die. A lot.