I’m not sure but maybe this one? https://www.mangago.me/read-manga/diamond_dust_yaoi/
https://www.mangago.me/read-manga/willow_love_story/
Only.modern day prince omega verse I know
Is this one??? https://www.mangago.me/read-manga/be_be_1/

It’s Omegaverse and all I remember is that the ml was known as the golden prince or something. Modern day not a historical or nothing