another world

MC gets reborn into a abandoned child and helps out other little abandoned childen

MC gets summoned with her childhood friend, the summornes said that her childhood friend (MC does not like her) is the long awaited shrine maiden. (also has a novel) https://www.novelupdates.com/series/the-white-cat-that-swore-vengeance-was-just-lazing-on-the-dragon-kings-lap/

MC gets reborn and is the fiancee of the wizard

MC gets reborn and is a "royal maid" at first then becomes a mother to Jill and maid to Sir Leonard (one of the most powerful wizards) https://www.novelupdates.com/series/from-maid-to-mother/

in process

(also has a novel) https://durasama.wordpress.com/arifureta-chapters/

MC is a spirit that can spirit in to monsters and animals (also
has a novel)https://tensaitranslations.wordpress.com/light-novel-projects/spirit-migration-web-novel/

Mc Betrayed by his own blood brother in war. After getting killed mc gets reborn into the body of his little sister.

A mysterious explosion killed an entire class full of high school students, the souls of everyone in class was reincarnated. MC discovered that she was reincarnated as a spider.