Board Thread:Boruto Discussions/@comment-25319479-20160502145551/@comment-1005735-20160505114002

Doesn't the page here say that Mitsuki has Jugo's enzyme? I'm fairly sure that Sage Transformation is caused by the enzyme's reaction to natural energy. Also I'm not sure why Mitsuki would give Boruto an eye that has on its own no power besides being covered in scales or why it would stay covered in it if he isn't actively pumping natural energy into it.

Off the top of my head Boruto like Mukai Kohinata may have only had one Byakugan because that is simply how far their impure Hyuga blood could take them, the eye could also be an implant from a relative or given the wound to Boruto's eye it may be to damaged to function properly.

The eye marking is part of Boruto's tattoo which is still spreading up his face the panel before, it only reaches his eye proper in the panel it activates, Kawaki has the same marking around his eye the entire time so the marking itself is unrelated to Boruto's eye.

Certainly nothing is confirmed but there are just to many breaches in logic and story consistency thinking to consider it to be Sage Transformation while the idea that its a Byakugan seems far more likely and thematically appropriate.