Like in almost every game Pokemon Sun and Moon also has unused content that never made it into the game. Here are some of the key things that never made it in or that could down the line.
Unused Mega Stones
Aggronite
Altarinite
Ampharosite
Audinite
Banetite
Beedrillite
Blazikenite
Cameruptite
Diancite
Galladite
Gardevoirite
Heracronite
Houndoomite
Latiasite
Latiosite
Lopunite
Manectricite
Mawilite
Medichamite
Mewtwonite X
Mewtwonite Y
Pidgeotite
Steelixite
Sceptilite
Swampertite
Tyranitarite
Unobtainable Z-Crystals and Z-Moves
Pikashunium Z Ash-Pikachu Thunderbolt 10,000,000 Volt Thunderbolt Electric Special 195
Mewnium Z Mew Psychic Genesis Supernova Psychic Special 185
Marshadownium Z Marshadow Spectral Thief Soul-Stealing 7-Star Strike Ghost Physical 195
Pokemon Go gift
Thank you for playing Pokémon GO! Please pick up your gift from the deliveryman in any Pokémon Center.
Thank you for playing Pokémon GO! You have already picked up your gift from the deliveryman.
Full list of cut content here
To be honest I think Gamefreak will make players buy Stars if they want all the mega stones and hidden abilities. As for the the Pokemon and Z moves I think they will be handled much like the Gen 6 movie trio where they where released near the time the set movie came out. So this could point towards another movie with that other Ash and then one true Gen 7 movie with the anime's Ash.
Unused Mega Stones
Aggronite
Altarinite
Ampharosite
Audinite
Banetite
Beedrillite
Blazikenite
Cameruptite
Diancite
Galladite
Gardevoirite
Heracronite
Houndoomite
Latiasite
Latiosite
Lopunite
Manectricite
Mawilite
Medichamite
Mewtwonite X
Mewtwonite Y
Pidgeotite
Steelixite
Sceptilite
Swampertite
Tyranitarite
Unobtainable Z-Crystals and Z-Moves
Pikashunium Z Ash-Pikachu Thunderbolt 10,000,000 Volt Thunderbolt Electric Special 195
Mewnium Z Mew Psychic Genesis Supernova Psychic Special 185
Marshadownium Z Marshadow Spectral Thief Soul-Stealing 7-Star Strike Ghost Physical 195
Pokemon Go gift
Thank you for playing Pokémon GO! Please pick up your gift from the deliveryman in any Pokémon Center.
Thank you for playing Pokémon GO! You have already picked up your gift from the deliveryman.
Full list of cut content here
To be honest I think Gamefreak will make players buy Stars if they want all the mega stones and hidden abilities. As for the the Pokemon and Z moves I think they will be handled much like the Gen 6 movie trio where they where released near the time the set movie came out. So this could point towards another movie with that other Ash and then one true Gen 7 movie with the anime's Ash.