This information comes from Eiji Aonuma…
“So yes, there were rumors like that, and we did discuss as a staff as to what would be possible if we took that route.”
– Aonuma said his team considered what they deemed to be the simplest option; making princess Zelda the lead character
“We thought about it, and decided that if we’re going to have a female protagonist it’s simpler to have Princess Zelda as the main character.”
– This idea was ultimately rejected,
“…if we have princess Zelda as the main character who fights, then what is Link going to do? Taking into account that, and also the idea of the balance of the Triforce, we thought it best to come back to this [original] makeup.”
– He also mentions the balance of the Triforce as a reason behind their decision