Board Thread:Theories and Speculation/@comment-30168130-20161223235115/@comment-25632268-20161225115212

Hashirama's chakra does not have Mokuton release. Hashirama has the affinity for water and earth and his kekkei genkai allowed him to mix earth and water together and create Mukoton. But you are assuming it is the same with bijuus, while I think bijuus have special releases by default, when Hagoromo created them he split the chakra that way.

Sharing Sharingan just by chakra was messed up, but again, Kishimoto rushed the ending and whole Kaguya's part is not well written nor explained.