If I have both Sun and Moon can I transfer one to each? Or would I need to possibly delete the demo and redownload? Or is it not possible to have multiples at all? Thanks for the help in advanced.
You can transfer ash-greninja multiple times! Keep in mind that only each game cartridge can only have one ash-greninja each. You do not need to delete and re download the demo. You can also transfer the items multiple times to different cartridges!
