As predicted, Leafeon-GX will be in SM5 Ultra Sun and Ultra Moon! This means Glaceon-GX will probably be in the set as well. SM5 releases in Japan on December 8th. Thanks goes to Jake C. for the translation!
Ability: Nature’s Breath
Once during your turn (before your attack), if this Pokemon is your Active Pokemon, you may heal 50 damage from 1 of your Pokemon with Energy attached.
[G][C][C] Solar Beam: 110 damage.
[G] Grand Bloom GX: For each Basic Pokemon on your Bench, search your deck for a card that evolves from that Pokemon and put it onto that Pokemon. (This counts as evolving that Pokemon.) Then, shuffle your deck. (You can’t use more than 1 GX attack in a game.)
When your Pokemon-GX is Knocked Out, your opponent takes 2 Prize cards.
Weakness: Fire (x2)