>>32465170I've done it a few times with an AR as well, in some cases it doesn't crash if you encounter Onix and Steelix for example. But most of the time the game crashed because it tries to play 2 entirely different animations or the shiny animation twice.
I'm not even sure why, since if you send out 2 shinies of your own it works fine, but wild encounters not so much.
I doubt OP would be this lucky, but I never messed around in Eterna Forest with an AR to know if it'd crash with those 2 mons in particular.