I actually managed to find someone who helped me out on that and traded me them.

Don't care. I did nothing wrong except try to complete my Shiny collection and I'm getting wrongly punished for it!

Until you can verify that the person who "Helped" you didn't hack the shinies themselves, it's kind of obvious why you've been soft banned.
And considering there was an exploit early on to change a Pokemon into a shiny (As well as duplicate items), yeah, the game recognizes they've been manipulated.

And you're naive enough to believe those people willingly traded you legitimate shinies?

Wasn't talking about Shinies, I was referring to the Mega Stones in that statement.

But the illegitimate shinies are likely the cause of your softban, not to mention it's likely someone hacked the stones in for you too

No. I got the Mega Stones legit, a friend on TFW was able to accumulate enough BP to get them all and kindly traded me them.

They're one time items and you only have the guy's word, not to mention it doesn't refute illegitimate shinies

I didn't get any Shinies with them, he put them on some of his regular Pokémon, I took the stones off, then traded them back to him.

Also fortunately I'm unbanned again. Yay.

I'm talking about your other shinies through trades

They're also legit, I made double sure to ask before trading.