Following the recent release of the Mewtwonite Mega Stones and this week’s release of Beedrillite and Mawilite, The Pokémon Company has put out a note regarding usage in Pokémon Sun and Moon on Battle Spot. The Mewtwonite X and Mewtwonite Y are currently unable to be used in Free Battle and Rating Battle on Battle Spot, though this will be rectified soon. It also notes that the Beedrillite and Mawilite will be usable in Free Battle on Battle Spot immediately after it releases, but they will not be usable in Rating Battle until Season 3 of the battles begins on March 21.
Source: Serebii
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