Perfect Blue is widely hailed as one of the greatest and most influential anime films of all time. You can actually read about the influence it (and other Satoshi Kon films) had in Hollywood HERE, but I think there’s another piece of media Perfect Blue had an impact on: The Legend of Korra.
PB is about a young woman, Mima, who decides to give up being a pop idol and instead become an actress in a rather seedy production. The stress and pressure of the new part (including a part where she has to film a rape scene and it feels TOO real) begins to wear on her, and the ghosts of her past eat away at her. Most notably, she keeps seeing a vision of her old self, who routinely taunts and haunts her. Mima begins to lose her grip on reality and then shit hits the fan. I can’t really explain the film because it’s so off the wall, but I think I got the basic gist of it.
I think something really similar happens in Korra; at the beginning of the fourth season, Korra is still reeling from a traumatic incident (also akin to a rape scene). She gives up being the Avatar (like Mima gave up on being a pop idol) and is trying to pursue her own path, but every time she tries to move on, she’s visited by the ghost of HER past; a dark version of herself, when she was poisoned and tried to kill her attacker.
This apparition (like in PB, it’s not clear if it’s real, or if it’s in the character’s head, or something else entirely) also taunts and haunts Korra, relentlessly following her and preventing her from getting better. It drives Korra over the edge and nearly kills her. Both Mima and Korra have to fight against this new apparition, even when it takes the form of someone they know who has a personal grudge against them.
These women tell the main character that she is worthless and not needed anymore and essentially not REAL, and they can be replaced. Ultimately, the heroines decide to save/spare the lives of their enemies, stop hallucinating, and are very confident in their identities (at least for Korra; Mima’s case is a little more ambiguous).
It’s a little hard to make a written comparison since most of the parallels are more visual (and there are probably other parallels I missed), so I recommend watching the first few episodes of the fourth season of Legend of Korra and Perfect Blue to see for yourself.