Make your bets. We saw very little on the last trailer that could point with precision, but here i go:

1- Sailcloth -
We saw sailcloth during the footage. This item was only introduced in Skyward sword and it was never present in the future. This could point to a game closer to SS and before OoT.

Another possibility
In SS Zelda mentions that legends tell that the goddess once gave a Sailcloth to her chosen hero, though the one Zelda gives to Link is obviously a different Sailcloth. This could point to a game before SS, before people having to flee to Skyloft. I doubt Nintendo would go this way, though.

2- Death Mountain -
It could be my impression or the sun light, but Death Mountain looked active. This happens in OoT, Four swords, Twilight Princess and ALBW. Could mean something. 

3- The world -
This was clear since E3, but this can't be WW timeline because it doesn't have enought 7.8 on IG... water, i meant water.

What do you think?

Right after Skyward Sword.

I'm going to assume after Ocarina of Time before Twilight Princess. Or after TP before FSA. Or before Zelda 1. Which is very plausible.

it's after skyward sword

Gee thanks.

Part of the adult era. Before WW or after Phantom Hourglass.

EDIT: Actually... I will change it later. Just thought about stuff.

Probably after SS then

My current guesses:

• Between Skyward Sword and Ocarina of Time
• Between Majora's Mask and Twilight Princess
• After Zelda II

Personally I kind of hope that the game itself gives little indication of when it would take place, and that if asked Aonuma just says he doesn't know and he doesn't care.

Probably after SS but before OoT. Very difficult to guess this with the limited info we have. It's basically a shot in the dark, lmao. The tech in this game seems way more advanced than most Zeldas though. Could mean something.

Poll added.