2 ML syndrome

But if he ended up w the fl doesn't that make him the 1st ml....?

exactly

I think I understand what you mean. As in "FL doesn't end up with who seems like the main love interest but with the one who seems like the 2nd male lead" right? If so I have a few:
https://www.mangago.me/read-manga/secret_alliance/
https://www.mangago.me/read-manga/undercover_chaebol_high_school/
https://www.mangago.me/read-manga/philia_rose_the_prophecy_of_the_crown_of_thorns/
https://www.mangago.me/read-manga/crimson_karma/
https://www.mangago.me/read-manga/actually_i_was_the_real_one/
https://www.mangago.me/read-manga/do_you_need_salvation/ (the manhwa adaptation officially changed the endgame from the og!ml to 2nd ml)

Thanks (=・ω・=)