So, I was on Discord and I saw someone say that Pokeballs effect natures. I didn't think that this mattered, so I'm a bit confused. Anyone mind confirming if it's right or wrong? Thank you for your help!
I have not heard of such a thing before. See Bulbapedia for how natures are determined,
Furthermore, there is no mention of affecting natures on the Pokeball page.
The only way I know of manipulating a nature of a Pokémon encountered in the wild is by leading your party with a Pokémon have the ability "Synchronize" and the desired nature. However it is not always guaranteed that this works (50/50).