The only sources I have found do not say anything about vanillite being able to learn water pulse other than from breeding it with snorunt, glalie, or froslass and they can only learn it from 4th gen tm. So, I am confused on whether or not it is even physically possible to get a vanillite with water pulse on sun and moon. Due to the fact, that Pokemon Bank does not work with sun and moon yet, does this mean I am just going to have to wait until Pokemon Bank becomes compatible and then do a boat load of transferring?
No, you unfortunately won't be able to breed a Vanillite with Water Pulse until the Bank update. Well, unless you decide to cheat, I guess. Sorry.