Japanese Global Link site says. This will allow players to gather and use even more of these special battle items, which were introduced to the franchise with Pokémon X and Y.
In order to receive these Mega Stones, players must participate in online competitions. The first of these campaigns will take place in late February, according to the Global Link. Those who take part will receive the Mega Stones for Mawile and Beedrill as a gift.
More Mega Stones are due in the future, with no timeline or further details yet specified. All future giveaways will include Mega Stones not already available in Sun and Moon, however.
Although Mega Evolutions and their accompanying items were a major part of the storyline in Pokémon X and Y, they took a backseat to the new Z-Move mechanic in November’s Nintendo 3DS follow-ups. Mega Stones are still available in Sun and Moon, albeit not until a player has completed the bulk of the games.