Megas Needed

So I have a lucario and gardevoir on my team and I want them to mega evolve I looked at the insurgence wiki and no mega stone for lucario and gardevoir to be found or at least no one has written yet how to find it, pls. help it will be greatly appreciated. Thank You.

Ok I can get the gardevoirite but for the lucarionite It says i need to use relic song so do I need to catch meloetta first? I have about 3-4 mysterious scrolls to find and catch meloetta

Yes, you get Meloetta DNA after catching it.

Ok thanks again