You can try fanfiction.net. It has a large collection of fanfictions including those related to Elijah and Elena. Just use the search bar and type in their names.
There's also 'Elena's Choice: Elijah or Else' which explores the idea of Elena having to make a difficult decision between Elijah and other aspects of her life. The story is filled with tension and drama.
In most Elena Elijah Lemon fanfic, Elena is often a central figure, with her own set of goals and emotions. Elijah, on the other hand, has his own backstory and motives that interact with Elena's. The lemon can also be a character in a sense, for example, if it has some kind of sentience or special power that affects the relationship between Elena and Elijah. It might be a source of conflict or a means of bringing them closer.
Well, first of all, Elijah would be by Elena's side all the time. He would help her with her daily needs, like getting things she needs or helping her move around when she becomes less mobile during the pregnancy. He would also share his knowledge of the supernatural world with her, so she can better understand what might be happening to her and the baby, and together they can prepare for any challenges that might come their way.
A really interesting fanfic could be set in a post - apocalyptic world where Elena, Elijah, and a lemon (maybe with some magical properties) are the key to saving the world. They face many challenges and have to rely on each other's strengths. This type of fanfic often has a lot of action and suspense as they fight against the odds.
I really like 'Elena and Elijah's Uncharted Journey'. This fanfic takes them on an adventure outside of Mystic Falls. It has a lot of great dialogue that makes their connection seem very real and deep. The author does a wonderful job of building the story around their relationship.
Love is a very common theme. Their relationship, whether it's a budding romance or a deep platonic love, is often explored. Another theme is the idea of sacrifice. Given the complex situations they are often in, one or both may have to sacrifice something for the other.
A fanfiction could explore the idea that Elijah's desire for Elena is part of a bigger prophecy. Maybe there's a hidden message that says if Elijah and Elena are together, it will bring peace to the vampire and human world. So he's driven by this sense of duty as well as his personal feelings for her. This would lead to a lot of internal conflict for Elijah as he tries to balance his feelings with the potential consequences of their relationship.
One idea could be that Elijah tries to court Elena in a very old - fashioned and gentlemanly way. He might take her on trips to historical places he has known over the centuries, sharing his stories and knowledge with her. This would be a contrast to the other vampires' more aggressive approaches towards Elena.
Another theme is loyalty and betrayal. Given their complex relationships and the world they live in, there are often situations where loyalty is tested. For example, Elijah's loyalty to Klaus might be put to the test because of his feelings for Elena. And vice versa, Klaus might feel betrayed if Elijah gets too close to Elena.