This was initially prompted by an ask requesting fic recommendations from my tumblr blog in 2024. Several of these fics have since been updated!
Naruto:
- Morpheme by infraredphaeton features a poisoner OC/SI who saves Sakumo. It's archive locked so you need to log in to AO3 to read it.
- Fallow Fields by zarinthel is about Kakashi's sister who becomes disabled during the war.
Bleach:
- freedom above all things by hellbeast is a worldbuilding heavy, Grimmjow-centric SI/OC fic I enjoyed.
Fullmetal Alchemist:
- A Pocket Full of Posies by lulu_lisbon is a SI/OC fic about a person who invents an alchemical array... and then gets conscripted to fight in Ishval. It's finished at 28k words and it's one of the shortest on this list.
X-men:
- I don't read a lot of X-men fics, but Pound the Table by An_October_Daye is really fun! This SI/OC is a mutant attorney.
MCU:
- If you like iddy fanfics, you might try rip to him but im different by victortor. It's a self insert as Loki, but it's kind of about the relationship between Loki and himself too.
Harry Potter:
- The Company of Another by sleipnirismybaby is a Petunia Dursley SI/OC which I find conceptually interesting.
MDZS/Untamed/Grandmaster of Demonic Cultivation:
- 江山如有待 | It Seems the Hills and Rivers Have Been Waiting by ScarlettStorm is less a SI and more an OC fic. This one IS romantic, so keep that in mind for if that's really a hard nope — it's a lengthy Jiang Cheng × OC romance about a buff wuxia girl in a xianxia world. It's a fairly traditional romance plot.
- by foot it's a slow climbby vroomian is more of a traditional SI/OC story. Good fun! Very iddy. It's archive locked so you need to log in to AO3 to read it.