@RyuShinobi500 yep, this can be called as joke, since normally pokémon trainer should not know what kind of pokémon inside an egg
@Chary im afraid about it, but no, this happen when i made some change on save file by editing with hex editor , an "egg glitch" could be happen, for example if you just have 2 pokémon on your party, the first pokémon has "assist" move, and the 2nd is an egg, you could identify what type of pokémon inside the egg, without using any cheats
@IncredulousP when i using pkhex or kind of that, when i enables predefined cheats from usrcheat collection you can call it "cheats" . BUT here, i just randomly editing save file using hex editor which is DIRECTLY editing sav file without any known interfaces, just to wonder what happen when i edit the .sav file, fill up blocks with some chars, just like when you debugging using nocash gba (in realtime)