Elijah's supernatural children would be teens when he finds them in season 3 of The Originals, Xavier at 17 and Zues freshly at 17. And his teens would also have many interactions with the supernatural community and many impacts consequently. The two don't trust each other, much like Light and L. And their relationship would be similar, including the heavy tweaks I have placed, rather shoved in the book.
There is much more to these characters than mentioned, such as backstories and what place they take in the vampire diaries universe.
And then I realized, it's fan fiction. I can do whatever I please. The reason most of us had started writing. And my character inspiration wasn't illegal. And there were no checkmarks that had to be met. I wouldn't have finished this story If I hadn't went with my original plan (being the character inspiration, that is the leading point to the plot.)
If you were here for the romance, you would still enjoy it. There would be more emotional connection, hence drama, ergo enhance the love story. And the situation I attempted to craft, but not yet richly developed would be significant.
My main characters would be Elijah Mikaelson, Xavier King, Zues Mikaelson, and Anastasia Mikaelson. The characters I would use often are Marcel Gerard, Camille O' Connel, Josh and Davina. Kol will also be included as I like the unfinished drama going between Elijah and his younger brother and other ideas that follow.
The Mikaelson family will be sprinkled frequently. And Vincent Griffen would also be used and many other characters that I believe would be impacted by the arrival of Elijah's children.