From sidekick to bigshot It is a novel with a Genius MC that to a certain degree remains lowkey. As someone with frightenly high IQ and frightenly low EQ there is one thing she knows. Her brain is a dangerous weapon. Her own (transmigrated) family has no idea how smart she is untill much later. She certainly tries to hide her identity from the world. Miracle Pill Maker Bullies the Boss Here the MC dies but gets reborn in the same world. Originally the most talented deciple of modern acient medical clan she does everything to hide as to not be taken back. There is just a small defect and that is her nature to walk on the edge of the law. She is lowkey in she does not want to be matched to her original self but she is high profile to the people she comes into contact with... Basicaly I don't think both are what you are looking for because both are rather fake low key. Yet both have an interesting MC that might be worth it. I am however not sure if they are being translated...
It is not on the toxic side I think. She transmigrated in a book world. When she transmigrated she gets blamed for the fall of her brother. Unlike many other leads she passively accepts the blame while trying to get evidence. She avoids conflict just tries to solve the problem. The original FL of the book is not a good person but this is not a constant faceslapping plot. MC mainly silently tries to find harmony in their family and protects them in the ways she can. For me this story is in the petting / fluff genre. When it orginally came out on the site I read the mtl it was in the top 5 for most read stories for most of two weeks and it is currently ranked 11 most viewed in 2 months. So I think it is worth to try and jugde it for yourself. It should be translated by webnovel now cause it is webnovel cover