Well, they could be combined by having a magical portal that connects their two worlds. So Naruto could step through and meet Renesmee. Then they could go on adventures together, like exploring the forest around Renesmee's home or Naruto showing her his village.
In fanfiction, they could also be combined through a prophecy. A prophecy that states that a ninja from another world (Naruto) and a half - vampire - half - werewolf (Renesmee) must join forces to save all the realms. This would bring them together and they would start their journey. Along the way, they would face many challenges that would test not only their powers but also their friendship. They might have to deal with the distrust of others in their respective worlds who don't understand why they are working together.
Freya could also be a spirit or a deity in the Naruto universe. Naruto, who has had experiences with powerful beings like the tailed beasts, could interact with her. She might bestow some special power or knowledge upon him, and their relationship could develop as Naruto tries to understand and use this new gift while also learning more about Freya's nature.
Another way is to put them in a completely new setting. Imagine Naruto and Azula in a modern - day city. Naruto would have to adapt his ninja skills to the urban environment, and Azula would have to hide her fire - bending. They could get involved in a mystery or a fight against an underground organization, and their different skills and personalities would play a big role in the story.
They can be combined through a portal concept. A portal opens between the Naruto universe and the Transformers universe, bringing Naruto and Arcee together. Then they can work towards a common goal like saving both universes from a threat that spans across dimensions.
Perhaps Naruto is mistaken for a prophesied hero in the Jade Emperor's realm. So, he is given special treatment and tasks. But Naruto has to convince the Jade Emperor and others that he is from a different world and still wants to help. In the process, their characters interact and influence each other.
One way to combine their powers is through Naruto's chakra control and Doraemon's Propeller on Head gadget. Naruto could use his chakra to power the Propeller on Head, allowing for faster and more efficient flight. This would give Naruto a new form of mobility in addition to his ninja skills. Additionally, Doraemon's Translation Gum could be used by Naruto and his friends to communicate with characters from different regions or even different dimensions in the fanfiction. This would open up new storylines and interactions, as they could now understand and work with a wider range of characters.
The sharingan from the Naruto universe might be able to analyze the patterns of Ikaruga's power usage. A character like Sasuke could then teach an Ikaruga character how to better control their powers based on the insights from the sharingan. In return, the Ikaruga character could show Sasuke how to use their polarity powers in a more strategic way in combat.
In fanfiction, the combination could start with Sansa being intrigued by Naruto's strange appearance and abilities. She might ask him to teach her some of his skills. Naruto, being the kind - hearted person he is, agrees. As they train together, their relationship grows. Naruto could also introduce Sansa to the concept of different 'worlds' as he comes from a very different place. This could open up new storylines where Sansa tries to find a way to visit Naruto's world or they try to bring some of Naruto's world's positive elements to Westeros.
Edward and Bella could be important characters. As Renesmee's parents, they would likely be deeply involved in the situation. They might be worried about her well - being, try to protect her from any threats related to the pregnancy, and offer their support and advice.
Well, Naruto's Rasengan could be combined with a Shen Gong Wu. For example, if there's a Shen Gong Wu that can enhance the power of a spherical object, it could be used to supercharge the Rasengan. The Xiaolin Dragons' elemental powers could also be combined with Naruto's shadow clone jutsu. They could create clones that have the powers of fire, water, etc., just like the dragons.
The characters can be combined by having them team up. For example, Naruto and Luke Skywalker could join forces. Naruto's energy and determination along with Luke's connection to the Force would make a powerful duo. They could face common enemies like the Sith or rogue ninja. Another way is to have them teach each other. A Jedi could teach a ninja about the Force, and a ninja could teach a Jedi some ninja techniques.