In line with the last Mystery Dungeon having references to Shia LaBeouf and the like, I'll be disappointed if the next PMD (if we get one) doesn't have a stoner Litten NPC.

“In terms of the customization of the trainer, that was really kind of a special thing for the Kalos region, which featured this kind of motif of France and really focused on this beauty and fashion aspect, which is why it was a prominent feature in that game. For this game, we’re focusing on adventuring elements, so we don’t have the actual free customization of the trainer, but you’ll see the items you use throughout the game visually represented; for example, when you’re underwater, you’ll have this little mouthpiece that lets you breathe. So there’s some cool stuff for how your trainer changes clothes and puts on accessories throughout the game.”

“It’s really meant to give unique traits of personalities to the different regions. So with the secret bases, for example, they’re really popular in the Hoenn region. Everything we come up with always tie back into the themes of the games we’re working on, so with the original Ruby and Sapphire we had the theme of richness or abundance, which is in the name of the region: The ‘Ho’ part means richness or abundance in Japanese, and ‘enn’ means bonds, like the bonds between people and their Pokémon, for example. So it’s just reflecting the theme of the individual regions.”

i wonder if trainer customization past skin tones will be present again

Yeah, it's confirmed. They showed it off in the Japanese Pokemon Sun and Moon trailer.

will pokemon sun and moon teach you how to read