Maybe... As I said, the idea was for a discontinued fanfiction, so I don't actually want to jury-rig anything up. However, according to lore, the gift of being Dragonborn was bestowed upon a mortal as a gift from Akatosh and could happen at any time. I suppose it's possible for him to give that gift to two mortals. After all, if the Emperors were truly granted with dragon souls starting with Alessia, that would mean when they had children, there would be at least two or more at a time. (That's mentioned in The Book of the Dragonborn)

Basically the story plot was that there was a young Altmer in the Summerset Isles who discovered that he loved Kynareth, so he travelled to Skyrim in order to meet the Greybeards. He didn't know much about them, obviously -- only that they were spiritual elders and knew more about Kynareth than anyone else would. He didn't know that they only selected Nords, though. lol. But the Greybeards sensed that he was Dovahkiin, and they took him on as their pupil. This was like 50 years before the events of Skyrim. Then, true to Skyrim's events, the Last Dragonborn was travelling down Pale Pass in a cart. Only she wasn't a prisoner; she was a young Dunmer girl, pre-adolescent, and she was going to Skyrim with her father so that they could continue to worship Talos (they were born and bred like Imperials, and were really really simple shepherds). So then la la stuff happened and the Altmer ended up the Dunmer's bodyguard/mentor at the order of the Greybeards.

It's a pretty dumb idea with tons of plot holes, but I just liked the idea of a haughty middle-aged Dragonborn and a really dumb child Dragonborn defeating Alduin together. There were about a million other OCs too... and um, there was no romance, so... Not only was it getting totally out of hand, but it wasn't at all interesting. Failure!

(Your idea for an "Artificial Dragonborn" is super awesome, though)

Thank you so much, I can't even begin to explain how that makes me feel. I'm sure a comment like that would have made me continue writing immediately last year, or even at the start of February, but... I've come to realise that I had a very very unhealthy obsession for Skyrim. I could go into the details, but I won't. I'll just say I realised I was wasting my life. I'm too young to be caught in a trap like that, I need to get a grip and live life instead of Skyrim.

I hope that makes sense somewhat.

Dunmer Ambassador for Morrowind to help relations with the empire. 

I'd say lore friendly.

If I were to write a story connecting a lot of my Skyrim characters to each other (friends, siblings, spouses, etc.) and in that story there were multiple people who are Dragonborn, would it be lore-breaking? I ask this because I do recall the Greybeards specifically saying that your character was the "only one revealed to us so far" or something like that when you ask them if you're the only Dragonborn.

Thanks! 

If you go back a little in the thread Shor gives a good explanation to this question.

I believe it will be lore-friendly. The Book of the Dragonborn mentions that "The Emperors have done their best to dismiss this notion, but of course the Imperial succession itself means that at the very least there are two or more potential Dragonborn at any time: the current ruler and his or her heirs". There is also Miraak who is alive during Skyrim events so there are at least two Dragonborn. Being a Dragonborn is a blessing from Akatosh and who can possibly know the mind of a god...? 

Ah, I see it now. Thanks for the help!