If there is a popular anime screaming Astrology, it is definitely Sailor Moon! It is not a secret that the author of the Sailor Moon, Naoko Takeuchi, characterized the sailor scouts according to the sun sign they were born. While she may or may not intend them, there are also arcs in the Manga, Crystal, and Cosmos that describe well the significations of the planets in astrology; the Infinity Arc or the Mugen Academy Arc of the Manga and the Sailor Moon Crystal of the Anime is that one arc, and its plot revolves around Hotaru, Sailor Saturn's reincarnation. Here's the list of why the arc successfully and accurately presented the traditional significations of the astrological Saturn.
Saturn As The Author Of Orphanhood, Solitariness, & Hardships
As the newly re-awakened Sailor Saturn rose to the sky, she mentioned that she's always the unwanted guest. She also recounts the life of Hotaru as living a life of hardships, mentioning the fire incident that killed her mother but also emphasizing her miraculous survival as the fated event should have killed her too (so that Sailor Saturn ceases to exist).
Because of the severe burns, her father engrafted a robotic prosthetic, making her a human-cyborg hybrid. In a cruel twist of fate, Hotaru's father (another Saturnian figure in the plot) used her as the host for Mistress 9 (the consort of the arc's main villain- Master Pharaoh 90) as part of the alliance with the dark entity from a dead star system (the Tau Nebula); because of the infestation and of the robotic graft, Hotaru's always in pain.
As mentioned earlier, her father is a Saturnian figure (it is worth mentioning that Saturn is the natural significator of the father in a nocturnal chart). Unlike the 90s anime, as described by Sailor Saturn, Hotaru's father is a very ambitious scientist but unethical in his experiments. It was also him that summoned Master Pharaoh 90, selling his soul, causing the fiasco in Hotaru's life and the world at large in the Sailor Moon Universe. In her life as a student at Mugen Academy, students depicted Hotaru as an outright eccentric and often bullied her.
Saturn's Rejoicing In the Twelfth House & As The Traditional Significator of Death
The themes of the twelfth house and, as Saturn's joy, were central to the plot of the Infinity Arc/Mugen Academy Arc. From that, we witness a lot of witchcraft, demons, demonic possession, soul eating-stealing, parasitic infestations, darkness, and the usual sense of doom and gloom associated with death and destruction.
The main villain, Master Pharaoh 90, also depicts the Saturnian significations of lack, emptiness, and void. In fact, the name of the villain's organization is "The Death Busters" and portrays Sailor Saturn's role as the guardian of endings, ruin, and death (and in the following arc, also of rebirth).
Saturn In The Domicile Of The Moon, Cancer
Hotaru embodies the detrimental position of Saturn, as she is physically frail. Sailor Saturn also mentioned that Hotaru's injuries from the fire incident and the implantation of Mistress 9's egg affected her, too.
Like all the arc plots, the main villain's object of interest is Sailor Moon's Legendary Silver Crystal, as it is the most powerful object or energy source in the Sailor Moon Universe. In the Infinity Arc, Mistress 9 and the Death Busters seek to have the Legendary Silver Moon Crystal because their life and energy source, the Tairon Crystal, is losing power, or it is at its end (again, we see the theme of the essentially debilitated Saturn into play). Drawing a parallel to traditional astrology, one can observe the goal of the villain akin to the themes of Saturn in Cancer - it is relying on, longing for, or desiring the powers of the Moon to survive.
For better context, Mistress 9 awakens and successfully took over Hotaru's body (yes, instantly turning her into a 30-year-old lady - also another notable Saturnian signification) upon detecting the Silver Crystal's presence. Starting at the upper right-hand side panel, Mistress 9 stole and ate Sailor Chibi Moon's soul and Silver Crystal (the paintings depicting the mythological and astrological Saturn eating a child also comes into mind). The actions further empower her and allowing her to bring forth to Earth her consort, Master Pharaoh 90.
In Modern Astrology, Saturn Is The Planet Of Limitations, Fortitude, Resilience, & Sacrifice
Unknown to Mistress 9, Hotaru's soul survived but is bound by the thorny chains. With her firm resolve to help, she eventually freed herself from the thorny shackles, returned Sailor Chibi Moon's soul to her body and her Silver Crystal, and saved the souls of the inner sailor scouts.
Unfortunately, Mistress 9 took advantage of the act and obliterated Hotaru's physical body, freeing herself from the host but resulting in Hotaru's soul to disintegrate. As Sailor Saturn and with the help of Sailor Pluto, she lead the escaping Pharaoh 90 to enter the portal to another dimension and in there sealed and destroyed him for good.