Yeah when you hatch an egg both TID and SID will be the same as yours so they'll be different from the original ones, making the result not shiny unless yoyr TID/SID make the egg PID (which is always 0x00000000 for Pokémon generated with that code) shiny (so for PID 0x00000000 you would need TID xor SID <= 7). The code to nickname any Pokémon of course doesn't change TID or SID so it will be fine