The Byakugan is a doujutsu which basically gives the user a near 360º field of vision except for one blind spot back of the neck.
Hyūga clan has been shown to pocess this doujutsu and Kaguya apparently had this Doujutsu.
Now according to the latest spoilers, Kaguya has been stated to had come from another dimension to partake of the Shinju fruit.
Kaguya Sharinnegan basically made her to travel through her six dimensions.
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But before she came to Narutoworld she obviously wouldn't have had sharinnegan considering she only awaken that doujutsu after she ate the Shinju fruit.
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Can we safely say Kaguya may had use her Byakugan instead to travel into Narutoworld?