Board Thread:Theories and Speculation/@comment-45444155-20200728155230/@comment-3279282-20200801034406

"Transformation" is a noun, not a verb. And the db states: Amongst the various Sage Modes, only those who have mastered the Senjutsu of Ryuchi Cave are allowed to wield [Kabuto's inorganic technique]. - In Jugo's village, the state after invoking the power of Senjutsu [e.g. Sage Mode] is referred to as "Sage Transformation". - special clan's ability to take in the power of nature and the source of that ability - Having found out that the origin of Jugo's power was the Ryuchido.

In conclusion, the Ryuchido teaches the way of attaining "Sage Mode", whereas the people from Jugo's clan can undergo the transformation without training, because of the enzyme. In their village, the resulting state is called "Sage Transformation", but is essentially a "Sage Mode" - the same Kabuto properly learned and Orochimaru failed to enter.