For Modern, I would say Flowers are Bait like Wenc mentioned. Also, Only Hope, Childhood Friend Complex or I’m Fine, Thank You, And You? are still ongoing.
But if you want something completed, Daytime Star, Live or Not, That Couple Has A Secret, or The Roommate Agreement, for example. Some are modern but with some fantasy/supernatural in it. With smut, Man With Ghosts or Demon's Wish. If you don't mind tragedy and historical, I would recommend Gorae Byul, it's pretty interesting.
If you don't mind if it's a manga, tragedy and historical, hotaru no yomeiri is pretty good and original but very sad.
Completely agree on Hotaru no yomeiri!
Modern: my family's Romeo(it's josei so maybe it has smut), veil (not so modern), falling for danger, the couple breaker, the time we were young( cringy Wattpad flashbacks but it's really good, translation sometimes sucks)
Fantasy: the male leads are trapped in my house(kinda historical), The Way to Protect the Female Lead's Older Brother(real good but I think it's dropped!)
Manhua: The Little Junior Sister Doesn’t Want to Ascend (doesn't show much romance but it's peak, cultivation/sect category and it doesn't have many chapters), only for love (you'll absolutely love this one and plus it's modern)
Not romance but Underworld restaurant! It's really good :3

i usually don't read straight romance but this made me feel so crazy i love them so much oh my god