After his death, Obito revealed the past of Itachi to Sasuke.
It made him one of the strongest ninjas.
This question may be a bit offensive to some Naruto fans.
Similarly, the two together managed to defeat Momoshiki Ōtsutsuki, who captured Kinshiki Ōtsutsuki, something else 4 Kage combined struggle.
When Itachi killed the rest of the Uchiha family, Sasuke was pressured to lose his family and what Itachi told him: that he had never loved Sasuke.
Sasuke uses this power frequently and allows him to instantly swap places of any two targets in a specific range.