Spoiler alert spoiler alert! The spoiler belongs to kokiri!
Actually, I think that they were already in the temples, but I am not sure. I am going to replay OoT to really find out.
Most of the Sages were in the area where the Temple was located but weren't originally in their respective temples but you know the basic story (they go into the temple to break the curse on it or something to that effect, Link comes along, and the new sage awakes).
However my vote goes to Shiek being able to see the future. Shiek knows her way around magic and is Zelda (who had a prophetic dream in the beginning). However Shiek might just be well informed (like Kaepora Gaebora and God I hope I spelled his name right) in the case of knowing that Link needs to go to the Temples, undo the curses, and awaken the new sages.
All in all I do believe that Shiek can see the future (because Shiek=Zelda and Zelda forecasted the things that Ganondorf would try to do in a dream).
Sheik/Zelda, in my opinion, doesn't see the future.
When you take the master sword and talk to Rauru, he tells you the ancient sages built the Temple of Light (the place where Adult Link talks to Rauru).
So, we know the sages are:
- Saria
- Darunia
- Ruto
- Impa
- Nabooru
- Rauru
- Zelda
As Rauru said, the sages built the temple of time, meaning Zelda met the other sahges while building the Temple of Light.
Well this is technically true but it was the ancient sages built the ToT (you even said so in your post). While Rauru is an ancient sage Saria, Darunia, Ruto, Impa, Nabooru, and Zelda are much to young to be the ancient sages.
How do you know this for a fact? My point is that we are aware that it is possible for one to travel through time, could Zelda/Sheik be able to? Yes, why wouldn't they? This would be a perfect explanation as to how Sheik is aware of these events, and why she always appears to be one step ahead on other situations.
I'm sure Zelda, being the one with the triforce of wisdom, would have the intelligence to take advantage of her ability to send Link back in time. This would mean that she can also send herself back, just because we never see it or are told, does not mean it doesn't happen.
Dvsag is correct, Lenora. Shiek can't travel through time like Link because you need the Master Sword and Link has the only one in existance. Shiek=Zelda however and Zelda has prophetic dreams so it's concievable that Zelda used her Triforce of Wisdom to harness those dreams to see the future whenever she wanted.
'But Kokiri if that's the case then why wouldn't she have seen Ganondorf trapping her?' you might say. Well there are two explainations for this. First and foremost she didn't bother (or didn't have enough power to) see that far ahead into the future. Second is that through seeing the future she is able to alter it and unexpected things might come of this or her visions might be completely avoided (like for instance she might've seen herself getting mauled by an octorok and avoided it).