Is there a tool for editing gift pokemon?

[MrShtok]

So I'm making a simple fire red rom hack for me and my friends which only replaces the Kanto pokemon with fakemon of my own. I want to change the gift Pokemon like the hitmonchan or hitmonlee you get and the eevee, lapras and more.
Is there a tool for doing that? like a software that automatically edits those for you? Pokemon game editor doesn't have that from what I've seen, am I wrong?
If there isn't a tool for doing that, how exactly do you edit these events? I tried looking at the scripts of those events in advance map but only for some of them it showed me the offset of the real pokemon I wanted to change. for some of them the offset of the gift pokemon was something like 0x4001 which is weird

 

[Asith]

Script editing is your best option, and since all you're doing is changing one species value, it's very easy.
As for 0x4001 and such, those are variables. They hold a changeable value, in this case a species value. Somewhere before that script, there's probably a command like setvar 0x4001 0x16. That command would put 0x16 into 0x4001, so whenever the script calls for 0x4001 it's using the value 0x16. There are other ways to put values in variables too, but hopefully knowing that is enough for these scripts

 

[MrShtok]

Script editing is your best option, and since all you're doing is changing one species value, it's very easy.
As for 0x4001 and such, those are variables. They hold a changeable value, in this case a species value. Somewhere before that script, there's probably a command like setvar 0x4001 0x16. That command would put 0x16 into 0x4001, so whenever the script calls for 0x4001 it's using the value 0x16. There are other ways to put values in variables too, but hopefully knowing that is enough for these scripts

Thanks!!
So how exactly do you edit the pokemon with the 0x4001 variable? for pokemon without this variable I can easily change the offset to the pokemon I want, but I don't know what to do when it comes to the pokemon with the variable.

 

[MrShtok]

Script editing is your best option, and since all you're doing is changing one species value, it's very easy.
As for 0x4001 and such, those are variables. They hold a changeable value, in this case a species value. Somewhere before that script, there's probably a command like setvar 0x4001 0x16. That command would put 0x16 into 0x4001, so whenever the script calls for 0x4001 it's using the value 0x16. There are other ways to put values in variables too, but hopefully knowing that is enough for these scripts

Okay lol I didn't read the rest of your comment correctly where you said how to do that nevermind Thanks!