Ataque! Princesa (2023)

Both are historical dramas with a poisoned and royal ML who brings the FL into his mansion and marries her.

Both are historical dramas in which the FLs are magical in some way and both MLs are suffering from long term poisoning.

Both are mini dramas with a historical setting and a royal ML who has been poisoned. Both FLs are determined to cure him.

Both are mini dramas with a historical setting and a royal ML who has been poisoned. Both FLs are determined to cure him.

Both are dramas with a historical setting and a royal ML who has been poisoned. Both FLs are determined to cure him. Both dramas have a tragic or ambiguous ending in which the ML loses the FL.

Both are historical dramas with a poisoned and royal ML who brings the FL into his mansion and marries her.

Both are historical dramas in which the couple marry, then fall in love. Both MLs have been poisoned and the FL cures them.

Both are historical dramas in which the couple marry, then fall in love. Both MLs have been poisoned and the FL is determined to cure them.

Both are short(er) dramas with the same actor as the ML. In both, the ML is human and the FL supernatural/has powers. At some point in the plot, the ML is poisoned and dying and the FL saves him by sacrificing either her life or her powers. SOL ends happily while AOP is tragic.