Horror Kid
Bob-omb
In my mind it is all very simple (flawed, not very unique theory ahead).
Zelda falls back in time to the age of Demise rising the first time, where she meets Hylia and Rauru. She manipulates stuff in the present where Link is fighting Ganondorf (final boss), so Link can come to her and fight Demise (final final boss) with her once and for all. Time loop / Ouroboros. Present bites the past bites the present.
Maybe she has to collect 7 tears in the past and Link 7 in the present to reach each other for the true endgame.
And then they are done with the shackles of the timeline for the next game.
Zelda falls back in time to the age of Demise rising the first time, where she meets Hylia and Rauru. She manipulates stuff in the present where Link is fighting Ganondorf (final boss), so Link can come to her and fight Demise (final final boss) with her once and for all. Time loop / Ouroboros. Present bites the past bites the present.
Maybe she has to collect 7 tears in the past and Link 7 in the present to reach each other for the true endgame.
And then they are done with the shackles of the timeline for the next game.