Wild Mega Pokémon For PLZA

I think that wild mega Pokémon would be so cool! They would be found around lumiose (I dont really know where but somewhere) And you would have to get their HP to red, just like wild tera Pokémon in Scarlet/Violet. After the Pokémon is in the red it would go back to its normal form. Only then you may catch it. And maybe as an added bonus they could mega evolve without a mega stone just with high friendship? But to probaly balance it out they would be extremly rare and hard to catch.

(THIS IS NOT A LEAK THIS IS JUST SPECULATION)