Another place to find them is FanFiction.net. There are many RWBY fans who post their works there. However, the quality can vary, so you might need to read the summaries and reviews before choosing a story. Some stories might be more focused on their relationship development, while others could be action - packed adventures involving the two characters.
Reddit can also be a good source. There are RWBY - related subreddits where fans might share links to their favorite Emerald x Mercury fanfictions or discuss the best ones they've read. You can join these communities and ask for recommendations. This way, you can get some insider tips on the really good fanfictions in this category.
There's 'Mercury and Emerald: A Different Path'. This fanfic takes a unique approach by exploring what would happen if they decided to break away from their original group. It's an interesting read as it shows their growth as individuals and as a duo.
You can start by looking on popular fanfiction websites like Archive of Our Own (AO3). It has a large collection of RWBY fanfictions, and you can easily search for those specifically related to Mercury.
One popular 'rwby emerald and mercury fanfiction' is 'Shadows of Doubt'. It delves into the complex relationship between Emerald and Mercury, exploring their backstories and how they came to be where they are in the RWBY universe. Another great one is 'Partners in Crime'. It shows their adventures and how they work together in various missions, with some really interesting character development for both of them.
A really cool fanfiction is 'Mercury and Emerald in the Realm of Shadows'. It takes them into a dark and mysterious realm where they have to fight to survive and rely on each other more than ever. 'Emerald's Secret and Mercury's Promise' is another good one. Here, Emerald has a secret that she's afraid to share, but Mercury's loyalty to her is unwavering. And 'Mercury and Emerald: Facing the Past' where they are forced to confront their past misdeeds and try to make amends while still being the characters we know from RWBY.
The RWBY universe itself is full of mystery and action. Fanfiction about Mercury and Emerald can add more depth to their characters and their place in this universe. It can also create new storylines that might not be explored in the main series, which is very appealing to fans.
There might be a fanfiction where Emerald and Mercury are forced to team up with some unlikely allies. This would create a lot of interesting dynamics as they have to adapt to new ways of working and new personalities. Maybe they start to see things from different perspectives and it changes their relationship for the better.
One popular 'rwby mercury x emerald fanfic' is 'Emerald and Mercury: Partners in Crime'. It delves into their relationship, showing how they support each other during their missions. It has some great character development for both of them.
Another option is to check out some RWBY - focused fan communities on Reddit or Tumblr. Sometimes, fans will share their favorite fanfictions or even write their own and post them there. You can join these communities and ask if anyone knows of any good Amber x Emerald fanfictions.
Another theme is growth. Many fanfics show how Mercury and Emerald grow both as individuals and in their relationship. They might face challenges that force them to change and adapt, which is a key part of these stories. For example, they could be in a situation where they have to question their previous beliefs and actions. This theme of growth adds depth to their characters and the story as a whole.
One common theme is loyalty. In many fanfictions, Emerald and Mercury are shown to be extremely loyal to each other and to their cause, whatever it may be in the story. Another theme is redemption. Some fanfictions explore the idea of them trying to redeem themselves for their past actions.