The focus is strictly on 1v1 romances. I won't budge on that: no harem stories and no 1vN. There are paired endings, and each arc is standalone. The characters have consistent personalities. What did you expect? They're all written by the same author.
Gong Shangjue X Jiang Ran (one has been plotting this for a long time; the other falls in love after marriage)
Scheming, yandere King Xuanye X Narcissus-like Ranshuang
(Delicate and affected X simple and naive, with wavering loyalties)
(Imprisonment trope)
Ying Yuan, the Eastern Pole Qingli Emperor X Yue Zhiyi, the little princess of Qingqiu and a nine-tailed fox (a political marriage to maintain peaceful relations)
Hot-tempered, devoted Jinwu Guard Commander Shang Bieli X Jiang Yunyou, who transmigrated here to start a romance
Shy, stammering Yu Sifeng X Ye Jiangli, who won his love over ten lifetimes, sweet and clueless
Gentle Judge Zhou Yian X Lin Chengzi, a judicial assistant temporarily transferred away (seeking to marry his white moonlight)
Cold and taciturn Zhang Qiling, a stone statue pining for his wife X Shen Qingwen, an immortal in Hanfu and a huge fan. Bonus arc: a princess and a fake bodyguard
Bonus Arc Two: Zhang Buxun, a Republican-era scholar X Shen Chuwei, a young lady from a prominent Republican-era family
Optimistic and proactive Sha Lele from The Breakup Masters X Qin Huai, who has cheat-like luck and is stingy yet impulsive
I was going to write stories about Mysterious Lotus Casebook and The Legend of Qingyun too, but I got lazy and lost motivation, so I'll write about some others first.