Yes, there might be some out there. You can start by looking on popular fanfiction websites like Archive of Our Own or Fanfiction.net. Search for the specific pairing 'Shirou Emiya' and 'Raven Roth' with the keyword'married' in the search bar, and you should be able to find relevant stories if they exist.
One possible plot could be them adjusting to married life in a world filled with the challenges and magic from their respective backgrounds. Maybe they have to face enemies together who are against their union, and they rely on each other's unique skills to survive.
Raven Roth may also be a character who has a mysterious past related to the dark arts. Maybe she was once involved with a group or a situation that had ties to Voldemort, but she has now turned against the dark side. Her knowledge of the dark arts, though dangerous, could be used to help Harry Potter understand his enemies better and find ways to defeat them. This complex backstory would make her a very interesting character in the fanfiction.
There could be. Fanfiction is a realm of infinite possibilities. Since the 'Harry Potter' series has such a large and dedicated fan base, it's very likely that someone has written a story where Harry is married to Raven Roth. You can try searching on popular fanfiction platforms like Archive of Our Own or FanFiction.net.
Well, it's very likely. Since Naruto and Shirou Emiya come from two different yet highly popular anime/manga universes. Fans love to create crossovers in fanfiction to see how characters from one world would interact in the context of another. Some of these fanfics might be really well - written and offer interesting takes on how Naruto could be like Shirou Emiya, perhaps in terms of their personalities, goals, or even their powers if some creative liberties are taken.
One possible plot could be that Raven Roth is a powerful witch from a far - off land who comes to Hogwarts as an exchange student. She and Harry Potter initially clash but gradually fall in love. After the defeat of Voldemort, they decide to get married and work together to bring about new reforms in the wizarding world, like improving relations between different magical communities.
His projection magic might be affected by the different magical rules in the Highschool DxD world. Maybe it becomes more powerful or has some new limitations. For example, projecting holy swords could have a different energy cost or be more effective against certain types of devils or fallen angels.
One common theme is the exploration of their different personalities coming together in a marriage. For example, Artoria's noble and sometimes aloof nature with Shirou's self - sacrificing and determined personality. Another theme could be how they deal with the challenges of their new relationship in a world full of magical and dangerous elements.
Since I haven't read the fanfic, it's hard to say exactly who Raven Roth is. But based on the title, Raven Roth is the one who breaks Naruto's heart, so could be a character created for this particular fanfic.
Shirou would fit in as a powerful and unique addition. His combat skills and magecraft would make him a formidable ally or opponent. He could use his projection abilities to create various weapons and tools, which would be very useful in the battles that often occur in the Highschool DxD world.