The foundation of Naruto is ocular jutsu, as those who wield these powers are typically stronger than those who do not. Additionally, some ocular jutsu can be credited with the origin of ninjutsu. The original bearers of ocular abilities were the Otsutsuki, and when they arrived on Earth, they brought these powers with them.
Humans in Naruto first acquired ocular jutsu after Kaguya gave birth to her two sons, Hagoromo and Hamura. Hagoromo eventually became the Sage of Six Paths and passed on his ocular abilities to his descendants. These descendants would later wield Dojutsu such as the Byakugan, Sharingan, Rinnegan, and, in some cases, the Rinne Sharingan.
For many viewers of Naruto, the Rinne Sharingan is a completely new concept. Some fans have even asked, “What is the difference between Rinnegan and Rinne Sharingan?” While they are two similar Dojutsu, there is a key difference: Genjutsu. Throughout Naruto, the Rinnegan has never been able to cast Genjutsu.
Disclaimer: This article reflects the author’s views and may contain spoilers.
How the two Naruto dojutsu are different, explained

The Rinnegan and Rinne Sharingan share many similarities, the most significant being their Otsutsuki origin. Both Dojutsu were brought to Earth by Kaguya and Isshiki, but became prominent once Kaguya bore Human-Otsutsuki hybrid children.
The Rinne Sharingan is a predecessor to the Rinnegan and Sharingan on Earth, first appearing in Naruto Shippuden when Kaguya unlocked it after consuming the fruit of the God Tree. In contrast, the Rinnegan is a Dojutsu integral to the Otsutsuki clan. Throughout many points in the Narutoverse, viewers can observe the Otsutsuki wielding Rinnegan.
The Rinnegan and Rinne Sharingan may look different visually, but many of their abilities overlap. Sasuke has employed Universal Pull with his Rinne Sharingan, a power that Pain has used countless times with his Rinnegan. However, with Rinnegan alone, one cannot perform an Infinite Tsukuyomi and travel through dimensions.
How they're similar, explained

The biggest similarity between the Rinnegan and the Rinne Sharingan is their origin. Both can trace their roots to the Otsutsuki and came into the possession of humans after the Otsutsuki interacted with them. Humans who unlocked the Rinnegan achieved this by combining Indra and Asura chakra.
Madara was the first person to unlock the Rinnegan by implanting Hashirama cells into himself. With his Rinnegan, Madara could absorb Jutsu. Pain could also do the same and repel Ninjutsu. When Sasuke unlocked the Rinne Sharingan, he gained control over all Nature Transformations, which Pain also accessed with his Rinnegan.
Hagoromo, Sasuke, and Pain could use the Chibaku Tensei, aka Six Paths: Planetary Devastation. Hagoromo utilized the Rinne Sharingan to seal the husk of the Ten-Tails and create the moon, while Pain employed the Rinnegan during his battle with Naruto.
Final thoughts
The Rinne Sharingan and Rinnegan are Dojutsu that originate from the Otsutsuki. After Kaguya consumed the Fruit of the God Tree, she unlocked her Rinne Sharingan. As a result, she also passed the Rinne Sharingan on to her son, Hagoromo. Later, Hagoromo would grant his Chakra to Sasuke, enabling the Uchiha to unlock the Rinne Sharingan.
In the Boruto saga, the Rinnegan has displayed different abilities than those seen in Naruto. This difference arises because most Rinnegan users in Boruto are Otsutsuki. Momoshiki can absorb Ninjutsu and redirect it. Jura from Two Blue Vortex can shoot Bijuu Bombs from his Rinnegan.
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