https://www.mangago.me/read-manga/tasuketa_yakuza_ni_nerawaretemasu/
https://www.mangago.me/read-manga/mobsters_in_love/
Although i don't remember the ages ig it's either 30s x 40s or 30s x 50s
https://www.mangago.me/read-manga/lovers_on_the_last_train/
https://www.mangago.me/read-manga/40_x_40_chikuwa_kaigi/
https://www.mangago.me/read-manga/midnight_rain_ctk/
https://www.mangago.me/read-manga/still_like_me/ ( i think they're both middle-aged? I forgott)
https://www.mangago.me/read-manga/it_can_t_be_mutual_love/
https://www.mangago.me/read-manga/shiba_to_tokizou_diet_hen/
https://www.mangago.me/read-manga/mark_1/ (i think they're both middle-aged? I forgott)

need recommendations of romance stories where they're both middle-aged. bl, gl and het are all okay