May 2, 2016, 12:46 PM
there isnt an %100 way to tell if a pokemons legit. in the case of jirachi there was event last month where they were given away in mass so it's definitely possible its legit. one way you could check is by going to the iv checker at the battle resort. hackers tend to give pokemon perfect ivs so if it doesnt have it its probably fine. the shiny mew i would be really scpiktical on as shiny event legendaries (such as mew) are incredibly rare.