If you’re not sure what “Genned Pokemon” mean, its basically a “Generator” that gives you the best IVs and Shiny Legendaries (Maybe). These Pokemon do not affect your game. Some people use Youtube or D i S c 0 r D. (Changed the name so I won’t get banned.)
Honestly, my thoughts on Genned Pokemon is that its not that bad! Its nice to get a few more Master Balls from them and good to get your version exclusive Pokemon. Tell me your thoughts!