Considering u have over 300+ in your already read idk if I can rec something u haven't read before, but I'll try.
Crack of Dawn is about tracking down the person who destroyed Lin Jian's village with a slow romance that doesn't rlly develop until later. https://www.mangago.me/read-manga/crack_of_dawn/
Not Blossom is about the oppression of Korean people during the Japanese occupation & past relationships are less so romantic and more so just supporting the theme https://www.mangago.me/read-manga/not_blossom/
Everything I read is pretty romance focused but feel free to check my favs list to see if there is anything in there that sounds interesting https://www.mangago.me/home/mangalist/2599337/

Please recommend me some shounen ai manhwa or manhua whose main focus isn't romance