1. Gen6: meganium and yanmega, gen7: porygon z (can't be z-moves because it was posted after the fact that z-moves were revealed and said that it wasn't revealed yet and are highly advertised) [POSSIBLE ANSWER\ RIDDLE POSSIBLY SOLVED- people are guessing some kind of transformation involving the z-rings, something called (fan names) z-forms, z-evolution, ect]
2. Yukie Nakama, a Japanese actress, and Kirsi, a protagonist in anime Darker than black, which don't point to the new pokemon directly(some kind of anime character, maybe a new dark type?) [ANSWERED/ RIDDLE SOLVED- silvadi]
3. "don't think you know everything about the starters just because of the latest news about their mid evolutions and the previous leak about their final evolutions. Of course, we're not talking about their skills, abilities, data, stats, etc. Some guesses(speculations is the word I want to use here) about the three starters are also not true. The descriptions of starters also don't make things fully clear, the is only one truth: You don't know everything about the starters at all." (Don't know if this would be considered a riddle)
4. Riddler posted a pic of Anabel
[POSSIBLY ANSWERED/RIDDLE POSSIBLY SOLVED- she could have a cameo or it's possible that the battle frontier will be in sun and moon some way]
5. Cipher code: "! [Zelda25],288"
[POSSIBLY ANSWERED/RIDDLE POSSIBLY SOLVED-a Sky island referencing to the Zelda 25 anniversary game, skyward sword]
6."It's a pokemon and its design will be focused on its mouth."