You can start by looking on fanfiction websites like Archive of Our Own (AO3). It has a large collection of fanfictions, and you can search specifically for ones involving Female Frisk and Female Chara. Another option is FanFiction.net, which also has a wide range of works. Just use their search functions and type in the relevant characters to find some interesting reads.
It often starts with curiosity. They meet in the Underground and are intrigued by each other. As they spend more time together, they start to trust one another. For example, Frisk might show Chara the power of kindness, and Chara might show Frisk some of the secrets of the Underground.
Often, there are themes related to self - discovery. Both Frisk and Chara have complex characters, and in fanfiction, they might explore their identities further in relation to each other. Also, themes of redemption can be present, especially considering Chara's somewhat controversial character in the original game. They might help each other to overcome past mistakes or traumas.
One common theme is friendship. Since Frisk and Chara are characters from the same game universe, their relationship development as friends is often explored. For example, how they support each other through various challenges in the Underground.
One popular theme is friendship. They might explore how Frisk and Chara form a strong bond in different scenarios. Another is adventure, where they go on quests together in the Underground world. Redemption is also a theme, like Chara getting a chance to be redeemed through her relationship with Frisk.
Love, of course, is a major theme. The love that develops between male frisk and female chara can be portrayed in different ways. It could be a slow - burning love, starting from a simple attraction and evolving into something deeper. Or it could be a more sudden, passionate love. These different portrayals of love add a lot of variety to the fanfictions in this genre.
Well, there are definitely some out there. Some focus on their shared experiences in the Underground. For example, a story could be about how they support each other through various challenges. Another might be more about their post - Underground life and how they adapt to the surface world together. It really depends on what you're interested in.
One common theme is redemption. Chara might be portrayed as having a troubled past, and Frisk helps him find a better path. Another theme could be growth, as they both grow as characters through their relationship. Also, adventure is a theme, with them going on quests together.
One common theme is friendship evolving into love. In many of these fanfictions, male frisk and female chara start as friends who have shared experiences in the Underground, and over time, their relationship deepens into something more romantic.
Well, I'm not sure about specific male frisk and female chara fanfiction off the top of my head. However, you could try joining some Undertale - related fanfiction forums. There, fans often share and discuss their favorite works. Maybe someone has written a great piece with this pairing that they can recommend to you.