Nature Code for US Soul Silver

[Lost Seraph]

I need a nature modifying code (or multiple nature modifying codes) that do 2 things:

1) Do not affect gender

2) Applicable to Pokemon I've already caught (not wild Pokemon)

I can't believe this hasn't been done yet. Seems to me that it'd be more complicated to make a code that does gender and natures instead of making them separate, and that's the only one I can find; the gender & nature mod code.

I suppose I could live with the gender + nature modifier code if we knew the side effects it had upon using twice (example: turn a male jolly Horsea into a female quiet Horsea then back into a male quiet Horsea) especially for Pokemon that require a specific gender to evolve or Pokemon with no gender like 5/6 of my competitive battling team.

[Gurluas]

The pokemon without gender actually have an internal gender.

[Lost Seraph]

The pokemon without gender actually have an internal gender.

So using a gender modifying code on a Kyogre would pose no problems at all?