Rey is the true Chosen One, unlike Anakin
Looking at all of the evidence, it seems pretty clear to me that it all points to Anakin being the Chosen One.
The Jedi may have debated it, and Obi-Wan (in Rebels) may have even thought it was Luke, but one must first look at all of the evidence beforehand.
Anakin was a Force-induced creation. His mother made it clear that she had no idea how she got pregnant (extremely similar to the virgin-mother principle that is found in numerous mythologies), and, for a while, it was "official" that Darth Plagueis and Darth Sidious manipulated mid-chlorians to create him. This last part is, at this time, not considered canon. That aside, his creation was Force-induced.
How do we know that he alone brought Balance to the Force?
After all, even Obi-Wan rightfully felt that Luke was the Chosen One.
But Luke did not destroy the Emperor. He extended MERCY to his father, and that unmerited gift presented an opportunity
to Vader. It was Vader, and Vader ALONE, that made the deliberate CHOICE
to rid the galaxy of the most powerful Sith who ever lived.
The point of showing Luke being helpless on the receiving end of Sidious' Force-lightning is just that: Luke was HELPLESS. He could NOT have defeated Sidious. Only Vader/Anakin could. With as little humanity as he had left, he lifted Sidious above his head and flung him to the core of the Death Star.
I don't believe that being a Skywalker means the galaxy can't be in Balance either. If that was true, then Anakin would've had to have murdered his son and daughter after he had slain Sidious. So, was there a confirmation that the Balance had been restored at the very moment that Sidious was killed?
Also, was there some kind of SIGN afterward to confirm that the redeemed Anakin was the Chosen One?
The answer is "Yes" to both questions.
At the Endor celebration, his Force-ghost appeared alongside Obi-Wan's and Yoda's. This happened without the TRAINING that Obi-Wan and Yoda received from Qui-Gon. This makes his ghost's appearance all the more "miraculous" an event. Qui-Gon's ability to maintain his consciousness (and only as a Voice) after passing into The Beyond was a major event. It indicates that something HUGE was happening at THAT time. Obi-Wan's and Yoda's later ability to project a super-consciousness in an observable form was even more momentous. Another major sign of just how epic the times they were active in were. So Anakin's being able to be there at the celebration is a very big deal indeed.
At the end of Return of the Jedi, the Force was in Balance.
Something happened afterward
to throw it out of Balance, and I postulate here viewtopic.php?f=2026&t=10026
that a large contributor to the destabilization of the Force was Luke's reestablishment of the old Jedi Order.
I touch on just a couple of examples of how thoroughly corrupt the Jedi Order was in that thread, so I won't repeat them here now. The main point being is that the Jedi fully believed that they were The Good Guys and shining beacons of being unified with the Light Side of the Force, when clearly they weren't. Their actions advanced great cruelty and barbarism, because they enormously benefited a measly minority of elite psychopaths. They were serving this function BEFORE Palpatine even became a Senator, when there was still a Republic, so imagine just how twisted their fruits were by the time Palpatine was the Supreme Chancellor.
There would have been no Emperor had it not been for the Jedi being the very tip of his spear.
Based on the very scant evidence we actually have, I can only conclude at this time that Rey and Luke will be the first generation of Force Adepts who will finally be beholden to maintaining Balance in the Force by observing Natural/Cosmic Law. For this to happen, the old/order-based and thoroughly corrupt ways have to be abandoned, for both the Light Side users and the Dark. Anything less will only ensure Chaos.