Slender Man Stand In is supposed to be about direct Expies of the The Slender Man Mythos character. However, I suspected that like Darth Vader Clone and Fauxba Fett, it was instead being used for any character who shared superficial similarities to Slender Man. Since the trope had only 48 wicks, I checked all of them. The results are as follows:

Wick check results:

• 4/48 wicks, or 8%, were an invoked Slender Man expy (the correct use),
• 12/48 wicks, or 25%, were of superficial visual similarities,
• 7/48 wicks, or 15%, were of visual and narrative similarities,
• 2/48 wicks, or 4%, had no similarities at all,
• 8/48 wicks, or 17%, were ZCEs or potholes,
• 12/48 wicks, or 25%, were indices, and
• 3/48 wicks, or 6%, were the laconic, a project sandbox, and trivia.

The wick analysis: As I suspected, most of the non-ZCEs were either "character looks like Slender Man" or "character looks like Slender Man and stalks people". The ZCEs were mostly asserting that the character looks like Slender Man or is based on him without explaining how.

The solution: With only 4 correct examples and only 11 if you combine it with the examples that were 'The Blank Humanoid Abomination who stalks people', this is not a viable trope: Slender Man likely just hasn't been around long enough to accumulate enough direct references yet. Either cut it, redirect it to ReferencedBy.The Slender Man Mythos, or disambiguate it between The Blank, Creepily Long Arms, Expy, Humanoid Abomination,and Stalker without a Crush.

1. Recap.Little Demon S 01 E 04 Popularity Origin Of Evil: Slimm Timm is a Humanoid Abomination that originates from a creepypasta where he hunts down vulnerable girls in the woods. He's even called a "slender man" by an online personality. Arabella has Chrissy summon him to the corporeal plane to try and "cancel" him for it. The fact that the other girls try to sacrifice Chrissy to summon him is also disturbingly similar to a real life incident where two teenage girls did the same thing, coming dangerously close to killing a third girl in Slenderman's name.
2. Recap.The Owl House S 2 E 12 Elsewhere And Elsewhen: A cryptid known as Lenderman appears briefly in Eda's book of urban legends as a one-off joke. He looks exactly like Slenderman except he lends things to people.
3. Webcomic.Switcheroo AU: Ronaldo sees a monster in the trees called "Slenderwoman" and posts pictures on his blog about her. Really it's just Spinel trolling him.
4. WesternAnimation.Super Mansion: The Halloween special "Drag Me to Halloween" has Robobot try to look up scary things and stumble upon a Slenderman ersatz called the Slimmerman.

1. Chalk Outline: An odd version in Miss Peregrine's Home for Peculiar Children: Due to them living in a time loop, Miss Peregrine goes out every day to shoot the same Hollowghast as it comes out of the Sea. She can’t actually see it, but she knows when it will arrive and after she shoots it with a crossbow it falls into a white outline on the grass that she presumably made earlier. No idea what a Hollowghast is or how it's similar to Slender Man
2. Western Animation: SuperMansion: The series' Halloween special is "Drag Me to Halloween", which has American Ranger date a woman who turns out to be a ghost, Robobot get possessed by the Slimmerman or rather, pretend to be as a Halloween prank, Black Saturn and the Groaner try to find women to sleep with at a Halloween party and Cooch enacts retribution towards a dentist who refuses to give out candy (and turns out to be holding children prisoner in his basement for not meeting his strict standards on dental hygiene. Almost certainly correct use, but doesn't have any context
3. Pantheon.Fictional Expies: Endermen, Godly Mantles of The Pale One (End Dweller)
4. Pantheon.Minecraft: Endermen, Godly Mantles of The Pale One (End Dweller) as Lesser Deities in the Hall of Fictional Expies (House of Derivatives)
5. PlayingWith.Badass Bureaucrat: "Fred" is the most badass bureaucrat there ever was... because they are a Slender Man Stand In arisen from the abstract concept of bureaucracy itself, and will descend upon anyone who dares to contravene any of the myriad rules and regulations they watch over; getting on their bad side, whatever your reasons, is not a good idea.
6. Recap.SCP Foundation SC Ps 200 To 599: If the addenda weren't there to clarify its origin and the various forms the entity takes, you'd be forgiven for thinking Bundle is just the Slender Man.
7. RunningGag.Max0r: Something Wicked is frequently referred to after Max0r comes across its secret level, usually whenever another secret level or pitch darkness is encountered.
8. YMMV.I Am Sophie: "Hate"/"The Hand of Hate" for the Slenderman Stand In. Named, of course, for the tattoo across the hand on his face.

1. Reptilian Conspiracy: XCOM: Enemy Unknown references this trope with the Thin Men, with shades of The Men in Black and Slender Man Stand In. They look mostly human, like unnaturally tall, lanky men in business suits, but Thin Men have patches of scales visible around their collars and sleeves, and their sunglasses hide slitted reptilian eyes. In their natural forms shown in XCOM 2 they're Snake People, but their masters have put them through extensive alterations to help them infiltrate Earth during the Alien Invasion. Thin Men gather intelligence, act as clandestine go-betweens for the aliens' ruling Ethereal caste as they pressure Earth's governments to surrender, and perform acts of sabotage. In-game, they tend to show up on Council missions to menace a VIP, and despite debuting early in the campaign, Thin Men are quite dangerous thanks to their high accuracy with their light plasma rifles, ability to jump up to seize high ground In a Single Bound, and poisonous spit.
2. Animation.The Haunted House The Secret Of The Ghost Ball: Given that the actual Slender Man shows up later, it's very unlikely that the ghost is a reference to him
   • At the beginning of "Invasion of the Iron Beast" Kanglim is seen fighting a tall, lanky humanoid ghost in a formal suit.
   • The actual Slenderman is another of the monsters faced by the protagonists.
3. Characters.Batman Rogues Gallery Part 2: Mr. Bloom is unnaturally tall and thin, has pale skin, wears dark clothing and wears a mask that makes it seem like he has no face.
4. Characters.Buddy Simulator 1984: Your buddy's true form is clearly going for the tall-pale-and-faceless aesthetic.
5. Characters.Doctor Who The Silence: Expy: Misuse, as they're a confirmed expy of a completely different character and you can only be an expy of one thing at a time
   • Word of God states they were inspired by Edvard Munch's famous painting The Scream (with expanded universe implying that this actually is a painting of a Silent and they have been behind its numerous thefts), as well as combining visual elements of both The Greys (facial features, skin colour, overall body shape) and The Men in Black (the tendency to wear suits).
   • They also end up taking after Slenderman, the latter of which was at his peak in popularity at the time of their debut. However it's unconfirmed if they actually are inspired by him or if this is a coincidence.They also end up taking after Slenderman, the latter of which was at his peak in popularity at the time of their debut. However it's unconfirmed if they actually are inspired by him or if this is a coincidence.
6. Characters.Miss Peregrines Home For Peculiar Children: At least in the Tim Burton movie. They are faceless, have tentacles, are invisible, and even wear suits. Burton wasn't even subtle about it.
7. Characters.Pico: Despite debuting about three years before Slendy, he manages to resemble him very closely, at least in his suited look in Newgrounds Rumble. ...How can it be a Slender Man reference if it predates him?
8. Characters.Sdorica Black Orb Characters: Only visually, though.
9. Characters.Transformers Prime Decepticons: Hmm. A tall, lanky, faceless, silent, enigmatic figure with long arms and tentacles? Sounds like a certain suit-wearing horror-story villain. To further drive the comparison home, the fanbase sometimes call him Slendercon.
10. VideoGame.Ghostwire Tokyo: Rain Walkers are a type of enemy that manifests as tall, humanoid entities that attack Akito on sight. They all wear black three-piece suits and carry umbrellas. While they have mouths, they are otherwise completely featureless with white skin.
11. WebVideo.I Am Sophie: The Hand Monster is yet another Humanoid Abomination in a business suit. Unlike Slendy, though, he's got a face... but after looking at it you'll wish he didn't.
12. WesternAnimation.Hidden Side: Nehmaar Reem, a major antagonist in the "Night of the Harbinger", is tall, with pale skin, and has tendrils on his back.

1. Characters.Identity V Hunters: Complete with a lack of a face and a tendency to stalk others.
2. Characters.Little Nightmares: The name's a giveaway, isn't it? Being a tall skinny figure in a dark suit with a shadowed face who pursues children for unclear but sinister reasons, he's pretty much just Slendy with a fedora, minus the tentacles.
3. Characters.Minecraft: A very self-evident example, if the name didn't already make it obvious. They are dark, extremely elongated humanoids with mysterious origins and intentions.
4. Characters.Super Smash Bros Steve: On top of Enderman's appearance being a dead ringer for Slender Man, it is also shown in its debut trailer sneaking up on Steve while he's asleep and ominously peeking into Snake's box, which also fit Slender Man's modus operandi.
5. Characters.Ultrakill: Something Wicked is a tall, long, and unnaturally thin humanoid that haunts a dark area and remains a mystery to everyone. Its eponymous level even is a nod to classic horror games like The Eight Pages, where you have to navigate a dark labyrinth searching for specific objects while being stalked by such a creature.
6. Characters.X Com Enemy Unknown: Tall, slender fellows in business suits with nothing but malicious intent for humanity.
7. Film.The Bye Bye Man: The Bye Bye Man shares a few similarities to the Slender Man, being a pale, Lean and Mean entity in dark attire who specifically goes after people who find out about his legend.

1. Characters.The 100 Girlfriends Who Really Really Really Really Really Love You 11 To 20: She binds herself to be as thin as possible, wears a dark and (deliberately) concealing outfit, hides her face behind her bangs, and is shown to be a subject of mystery and gossip in the school. Also, she has a habit of making herself disappear from other people's view. Meme has normal human proportions and long hair, while Slender Man is unnaturally tall and thin, has no face, and is bald. She doesn't even dress like him.
2. Characters.The 100 Girlfriends Who Really Really Really Really Really Love You 1 To 10: She has unusually long legs, wears a black jacket and tie, shows little (if any) emotions, and was the subject of school rumors before she began dating Rentarou. Also, her reasons behind maximizing efficiency in her life remain a mystery. As above, she is a regular human girl who doesn't even dress like Slender Man.

1. Fountain of Expies
2. Horror Tropes
3. Memetic Mutation
4. Obviously Evil
5. Our Cryptids Are More Mysterious
6. The Newest Ones in the Book
7. Slender Man Stand In
8. ImageSource.Internet
9. ImageSource.Live Action TV
10. ImageSource.Video Games M To Z
11. ImageSource.Western Animation
12. UsefulNotes.North America

1. Laconic.Slender Man Stand In
2. Sandbox.Fountain Of Expies Cleanup
3. The Slender Man Mythos: * Fountain of Expies: To the point where expies of Slender Man have their own trope: Slender Man Stand In.