I can’t add this novel on here since it belongs to a different site, but check out “steal the male lead”. It’s a world hopping novel. The endings (well, most of the endings) are sad, so feel free to check out this novel if you’re looking for a bittersweet novel.

Here’s the link to the website if you want to read it: https://chrysanthemumgarden.com/novel-tl/stml/