Pokébank has just been released and a lot of players are already starting to transfer their beloved Pokémon from the previous Generations into Sun and Moon. Albeit the restrictions associated with transferring Gen 1 Pokémon, there is actually a way to transfer Mew and even a shiny one via the Pokébank. This process will render any Mew to be Pokébank-compatible and be transferrable to Pokémon Sun and Moon.
Pokémon Sun and Moon: How To Transfer "Legit" Mew
Glitched Pokémon cannot be transferred via the Pokébank and so, in order to effectively transfer one's Mew, one must have to trick their own Pokébank into thinking that their Gen 1 Mew is a legit one, the one obtained from the event in Japan, through the use of arbitrary code execution with 8F. [Spoiler Alert]: This guide entails long and tedious process that involves multiple guides in order to accomplish.
Introduction: Regular glitched Mew cannot be transferred from Red, Blue and Yellow via the Pokébank since the Pokémon's ID Number has to be 22796 and its OT name must be "GF." In order to make Mew a "legit" one, a player must use an arbitrary code execution with the use of Red and Blue glitch item 8F.
Step 1: Obtain Mew
First off, get Mew using the Mew glitch. For those that didn't know, a player can get Mew in Pokémon Red and Blue using a simple glitch. Here's a tutorial video by Lawspec on how to do it.
Step 2: Obtain 8F
Here's a tutorial video made by TheZZAZZGlitch on how to obtain any glitch item including the 8F. It's also the easiest method to obtain 8F to date.
Step 3: Bootstrapping
Bootstrapping is meant to redirect execution to the third bag item upon using the 8F. This requires a specific party setup which will be listed as follows:
Exactly 5 Pokémon in the party
Pidgey as the first Pokémon
Parasect as the second Pokémon
Onix as the third Pokémon
Tentacool as the fourth Pokémon
Kangakshan as the fifth Pokémon
First Pokémon (Pidgey) must have a current HP of 233
Step 4: Execution
Crystal has made a detailed guide on how to properly execute all the programs as easily as possible. Here's the Item list corresponding to each 8F use. Next, in order to obtain more than 99 of a given item, one must use MissingNo. Or 'M for item duplication thus, the Old Man glitch is required. Take note that encountering MissingNo or 'M will increase the quantity of the player's sixth by 128 (given that the number is lower than 128). [Reminder]: Do not alter the quantity of items that can't be tossed.
Bonus: Obtaining Shiny Mew
Once the player successfully accomplished Step 4, he has already transformed Mew into a "legit" one, transferrable to the Pokébank. But before proceeding, a player can actually obtain a shiny upon transferring by altering Mew's DVs with the use of two additional 8F. Click here for the guide. By this point, one can swap the position of Mew on their PC with any other Pokémon and also alter their DVs to make them Shiny upon transfer.
End Product
After completing all of the steps (including the bonus Shiny Mew guide), the player's Mew in Box 1 should look something like this. Once it's confirmed, the player can now transfer his or her Mew into Pokémon Sun and Moon without Pokébank blocking the process! An alternative process can be shown in the video own below. Check back for more Pokémon guide and tips!