I don't read much Isekai anymore but here are some that left a heavy impression on me kr that i liked alot:
http://www.mangago.zone/read-manga/mairimashita_iruma_kun/
More Comedy based
http://www.mangago.zone/read-manga/when_a_stupid_fps_player_falls_to_another_world/
Interesting concept.
http://www.mangago.zone/read-manga/wortenia_senki/
I've only red the beggining but it seems pretty interesting. Martial arts)
http://www.mangago.zone/read-manga/saihate_no_paladin/
Rather sad story
http://www.mangago.zone/read-manga/saijaku_teima_wa_gomi_hiroi_no_tabi_o_hajimemashita/
Might know this one but it's pretty cute.
Get reincarnated as a monster/animal:
http://www.mangago.zone/read-manga/tensei_shitara_dragon_no_tamago_datta_saikyou_igai_mezasa_nee/
http://www.mangago.zone/read-manga/kumo_desu_ga_nani_ka/?HXjP
http://www.mangago.zone/read-manga/remonster/
Pretty well known but it's really good
http://www.mangago.zone/read-manga/tensei_shitara_slime_datta_ken/
Also pretty well known( has an Anime).
I also have another one i quite liked but i can't find the story haha
I recently posted a question about it and someonne found it.
It's:
http://www.mangago.zone/read-manga/mushoku_tensei_isekai_ittara_honki_dasu/?D2D2
It's a bit ecchi and hoestly a bit fucked up but I still enjoyed it haha.
But still tyvm! <3
Gimme some good Isekai/Reicnarnation/RPG-like stories. Except the known ones. I've read them all.