[Question] Change party postion

So, I haven't seen something asked like this before, let me get straight to the point.

So, the title is pretty self explanitory, Is there a way to change a Pokémon's party positon. i.e it checks for species kakuna, then, it moves that species into the first party slot. Swapping the first Pokémon in the party, to that certain species's party slot.

I tried to explain it as best that I could I hope you understand.

There's a thread I made in Relic Castle, as you can see I'm not that good at scripting so bare with me here.