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Seconded.

A far better pick than the extremely out of place World Break. Heck even Inuyasha makes more sense then world break in some cases for "Characters trapped in their past lives" with her being the reincarnation of a character in the show and been thrust back in time like that to more or less take her place

The only one I have a comment on really is the Manga (and subsequent adaptation into an anime) of World Break: Aria Of Curse For A Holy Swordsman

The reason for this is it does not qualify under the title of "Best Isekai Anime & Manga With Characters Trapped In Their Past Lives"

In the show and manga It's not that he's living out a life again. It's that he has brought forth into the present time his memories of his past, It's almost the same as if someone got comatose rather than traveled back in time.

Think the legend of Zelda breath of the wild, where we recover a bunch of past memories but in the present.

Otherwise this is a pretty good list

I see a couple of (Why no Re: Zero) comments.

I'm actually inclined agree with this list about excluding it, I love the show but it's protagonist isn't so much smart, as he is persistent in his goal and inclined to manipulate the situation with time over an over with trial and error until he gets where he wants or needs to be. It's the witch, Rem or others who help, not his intellectual prowess and Suberu himself is forced to admit this on several occasions. How he's just an average guy in an extraordinary situation.

He's nothing like say the protagonist from Code Geass. A character with nearly unsurpassable genius who not only ends up getting the superpower to manipulate people once in their life but uses it in extraordinary ways and even has to maneuver people and large organizations alike around a chess board in order to get to his end goal both with and without his power putting pieces here to incite other pieces to move the way he wants and such.

That's a far cry from Subaru's try, try again mentality. It's a good show, it's just not one with a protagonist who's notably and considerably intelligent.

I would go so far as to also say ascendance of a bookworms protagonist isn't really smart either, she's book smart. Literally, her only actual knowledge is on and about books and she loves them so much that she's willing to do anything to get them into her new world. She knows how to make them and is driven to get them, well the people around her are not aware of techniques that she knows or she again does things by trial and error to get her goal into reality. It's not so much she's intelligent in a way that's superior to others. She's just driven and has other information most in her possession wouldn't but out side of that expertise she's an average person.

However again in this situation I'm inclined to state that even she is far better than Subaru's average human intelligence a good amount of the time.

Anyways, thanks for reading and I hope we all! ❤