*on foreign wifi on mobile phone*

[@Pikmin Eye] I'm going to say "unclear" on that point. Cathia has been exchanging her Pokémon freely without consideration for any imaginary trainer-boundaries, like the ones you two have by ensuring you always have one Pokémon out each. You're currently in the midst of heated battle, there is no judge to call you out on it. If you decide to follow the same rules as Cathia, then yeah, you can. I'll keep how Cathia might react to myself, though. Teh-heh.