love is war
https://www.mangago.zone/read-manga/kono_koi_wa_hoshi_ni_wa_negawanai/ (a guy and a girl are in love with the same girl)
https://www.mangago.zone/read-manga/my_brother_and_i_are_rivals/ (a guy and a girl are in love with the same girl)
https://www.mangago.zone/read-manga/uso_no_tsukenai_otoshi_goro/ (a guy and a girl are in love with the same girl)
https://www.mangago.zone/read-manga/slightly_sour_secret/ (a guy and a girl are in love with the same girl)
https://www.mangago.zone/read-manga/kimi_no_love_wo_misetekure/ (girl A loves boy, boy loves girl B, girl B loves girl A)
https://www.mangago.zone/read-manga/i_wish_her_love_could_come_true/ (girl A loves girl B, girl B loves boy, boy loves girl A)
Faded first love but its not really a love triangle per se
this is so rare to come by but if u happen to find a manga/manhwa/manhua that is a love triangle w girl AND boy as both love interests then i am begging on my knees for the title,,,,, (i alr read katarina and her harem)