as a heads up not all of these are manhwa sorry
https://www.mangago.zone/read-manga/to_deny_the_route/ reborn into a game
https://www.mangago.zone/read-manga/kiss_the_abyss/ - not really reborn etc but mc transfers between irl & a game he made
https://www.mangago.zone/read-manga/i_have_to_be_a_great_villain/ reborn into system
https://www.mangago.zone/read-manga/again_1/ time reset, reborn to his younger self
https://www.mangago.zone/read-manga/dawn_of_the_dragon/ reincarnation
https://www.mangago.zone/read-manga/monochrome_rumor/ body swap (?) rebirth - two people die & one revives in the other's body
https://www.mangago.zone/read-manga/to_be_or_not_to_be/ mc got a life threatening illness, transmigrated to novel
https://www.mangago.zone/read-manga/don_t_press_the_button/ reborn as a bird(?)
https://www.mangago.zone/read-manga/turning/ time regression at death
https://www.mangago.zone/read-manga/how_to_survive_as_a_player/ not really rebirth, but transmigrated into a game
https://www.mangago.zone/read-manga/don_t_say_you_love_me/ time regression
https://www.mangago.zone/read-manga/i_became_the_lousy_side_top_official/ reincarnated into a novel or something
https://www.mangago.zone/read-manga/kill_the_lights/ mercenary reincarnated into an actor who the ML hates
https://www.mangago.zone/read-manga/approximal_guide/ guideverse, mc was someone the ml liked, reborn into the body of someone he hates
Tysm ( ˘ ³˘)
BL manhwa with reincarnation or reborn genre pleaaaase