It's a visual novel that likely involves a unique story. Maybe it has some interesting characters and a plot full of twists and turns. But without playing it, it's hard to say exactly what it's about.
Often, there's a theme of connection. It could be a connection between a family member and a baby through Ed Sheeran's music. Say, a father sings Ed Sheeran songs to his baby daughter, and it creates a special bond. Or it might be about a community where everyone comes together because of their shared love for Ed Sheeran's music and how it affects the local kids.
You might be able to find it on some specialized visual novel platforms or websites. Some popular ones like Steam might have it if it's been released there.
I'm not very familiar with 'Mister Ed Ed's Christmas Story' specifically. It might be a rather unique or perhaps a less - well - known Christmas - themed story. Maybe it involves Mister Ed, a character perhaps known for his own charm and antics, having some sort of Christmas adventure.
One interesting story could be about Ed and Winry's baby showing early signs of alchemy talent, just like its father. It might involve the baby accidentally transmuting simple objects and the couple's humorous attempts to deal with it.
One popular 'baby ed and al fanfic' might be those that explore their early days of alchemy training. For example, a story could focus on how they first discovered their interest in alchemy and the small experiments they did as children.
Themes in 'Kill Me Baby Sonya x Yasuna' fanfics can vary widely. Some may focus on the theme of loyalty, showing how the two characters are loyal to each other through different challenges. There could also be a theme of mystery, perhaps they encounter a mystery in their school or town and have to solve it together. And of course, the theme of character development is quite common, as fanfic writers like to expand on the personalities of Sonya and Yasuna beyond what we see in the anime.
You can try websites like Archive of Our Own (AO3). It has a large collection of fanfictions, and you can search specifically for 'ed and winry baby' fanfiction. There are often tags and filters that can help you narrow down your search to find the best ones.
To make it a good 'baby ed and al fanfic', include some elements of alchemy in a way that is accessible for their young age. Maybe they discover a simple transmutation circle and try to figure out what it does. Also, don't forget to add some emotional depth, like their bond as brothers and how they support each other even as little kids.