Reborn - scum
given action wu we dont see anything from any scum faction unless they are being blended in as town indictive or just genuinely all afk.
flavors mechanically shown:
Kyouraku
Isane
Mayuri
Byakuya
Central 46
Urahara
Aizen
outside of urahara if factual he should be indie
we have no real scum actions being displayed so kyoka is either the ability to hide all faction abilities or cloak them as fake claims wu.
so gin can possibly be mayuri or someone in gotei 13 everytime.