I'm not a sensitive person so idrk if these r crying material but soft sad (maybe?)
https://www.mangago.zone/read-manga/musebenake_junjou/
https://www.mangago.zone/read-manga/fangs/
https://www.mangago.zone/read-manga/isso_koe_ga_nakattara/
https://www.mangago.zone/read-manga/back_to_school/
https://www.mangago.zone/read-manga/back_to_school_all_grown_up/ (sequel)
https://www.mangago.zone/read-manga/10_years_where_i_loved_you_the_most/ (maybe? Idk it wasn't that sad)
https://www.mangago.zone/read-manga/taishau_wotome_otogibanashi/
It's not anywhere near the level of sadness of "10 years where I loved you the most", and some scenes were actually quite cute, but there are some scenes where your heart will clench and throb and tears will start threatening to come out of your eyes. It's not BL, but it's pretty damn good for a shoujo manga (even though I'm not a big fan of should manga)
well if you're fine with heartbreaking BL then
https://www.mangago.zone/read-manga/nigatsu_no_eden/
https://www.mangago.zone/read-manga/paradise_view/
https://www.mangago.zone/read-manga/hana_no_miyako_de/
https://www.mangago.zone/read-manga/kono_koi_ni_mirai_wa_nai/
https://www.mangago.zone/read-manga/life_senjou_no_bokura/
https://www.mangago.zone/read-manga/birthday/
https://www.mangago.zone/read-manga/lonely_to_organdy/
https://www.mangago.zone/read-manga/boys_love/
if you really want to sob a whole night then:
https://www.mangago.zone/read-manga/my_fiance_is_in_love_with_my_little_sister/
the novel is even worse.
Mangas that will make you cry