Manga Hunter here! I recently got into two light novels that had the same story premise kind of, but they had their own unique twist that made it interesting. One of them was even made into a online comic with beautiful art, but I recommend that the novel is read first since the art sometimes changes what the characters look like. If you guys like girls that were assassins in their previous lives and find ways to find revenge against people who have wronged them in their new lives, then give these a read.
Descent of the Phoenix : 13 Years Old Princess Consort by: Yi Shi Feng Liu (made into online comic)The strongest female assassin from a special assassination force met her death one day on a mission. To her surprise, she woke up in the body of a 13 year old girl, Mu Rong Liu Yue. Through Liu Yue’s past memories, she found out that she was bullied due to the huge birthmark on her face, even though she came from a renowned family. Liu Yue was beaten to death by her own cousin, and that’s how she managed to enter Liu Yue’s battered body. The assassin then decided to live her life as Liu Yue and swore to avenge her death.