I'm not entirely sure what 'inj3cting' specifically means here as it's an unusual term. It could potentially be a misspelling. If it was 'injecting', it might refer to women sharing or inserting stories in some context, like in a conversation, a writing project, or a social media post.
If by 'inj3cting' we think of it as sharing in a very engaging way, for example, a woman who is a survivor of a natural disaster might 'inject' her story of survival into the community by giving a very emotional and detailed talk at a local event.
Megumi Fushiguro is popular as well. His cool and reserved demeanor, along with his powerful cursed technique, attracts a lot of fanfiction authors. They might write about his relationship with other characters, like his unspoken bond with Yuuji, or explore how he further hones his skills in different scenarios.
Yuji Itadori is often a popular choice. His determination and unique abilities make for interesting time - travel scenarios. He could use his physical strength and Sukuna's power in different ways in the past or future.