Specifically, if I use destiny bond with a wobbuffett against Steven's Metagross in Ruby/Sapphire, will he go for the kill regardless, or will he switch to another Pokemon or otherwise play around it? I know they'll switch if they're perish-song'd.
No. The AI will not play around Destiny Bond. This is because the Gen 3 AI decides whether or not to switch before it uses a move based on what moves it can use and what timers will outright KO the AI's Pokemon that turn. Additionally the AI will not use an item to waste the destiny bond turn, and when the AI eventually does select a move Destiny Bond is not a factor into how the AI scores which moves are good to use. Even the best unmodded AI in Gen 3 can fall victim to Destiny Bond because of this.
My main source on battle AI comes from https://essentialsdocs.fandom.com/wiki/Battle_AI but I've also had experience where Champion Wallace outspeeds and KOs a Dusclops that used Destiny Bond the turn before.
