Generally messing with a pokemon's data directly will cause a pokemon to appear "hacked". IE force IVing, creating out of nothing, forced shiny, etc.ok so can someone answer these questions?
what makes a pokemon hacked?
and can hacked pokemon be parents of legit pokemon?
General smogon consensus is that "hacked" parents create "hacked" children. So no, even though technically no one would be able to tell.