In case you're curious... The code for that is as simple as changing a word.
0092 xxxx yyyy zzzz
0092 is the command to set the Pokemon speaking character (Such as chatot) as 'xxxx', and display their portrait (the picture) using expression number 'yyyy', and display that portrait at predefined location number 'zzzz'
So, to change it, all you'd have to do is change the expression number from whatever it is, to the number that represents "anger"
I do have a list of every command I know of in the game, but I'll release it once I know a bit more.
Thank you very much, Nerketur. That will help!
Also, in case you wonder why asked specifially for chatot, it is because me and a friend, one day when we were bored in class, we started what we call "Guild Stories", which is funny dialogs between the pokemon from the guild. And two of the pokemon were arguing (I think Loudred with someone, I don't remember clearly) and Chatot came to separate them and my friend said "Here comes the little plucked bird with the note on the head and when someone farts he wants to smell". Needless to say we were laughing the whole day after that. And now, with your tool, I can make that in the game! Thanks again!