I am currently running an Oriental Adventures (OA) campaign called The Divine Heir and the Jade Regent loosely based around the Pathfinder Adventure Path the Jade Regent with strong influences from Sekiro.  The first adventure is called The Ashina Legacy and is essentially The Brinewall Legacy set in and completely converted to an OA setting.

I had to rewrite the adventure intro and re-theme the monsters but it worked well.  Here is the flowchart of the adventure (and campaign).

I liked the idea of this NPC/Monster but she never encountered my PCs. I expect to reuse her at some point. A Karura is a Japanese harpy.

Medium monstrosity, chaotic evil
Armor Class 15 (brigandine)
Hit Points 88 (16d8 + 16)
Speed 20 ft., fly 40 ft.
STR                 DEX                CON                INT                 WIS                CHA
16 (+3)        14 (+2)        13 (+1)        14 (+2)        12 (+1)        16 (+3)
Saving Throws WIS +4, CHA +6
Skills Deception +5, Stealth +4
Damage Immunities poison
Condition Immunities poisoned
Senses darkvision 120 ft. (penetrates magical darkness), passive Perception 11
Languages Common, Draconic, Oni
Challenge 5 (1,800 XP)

Dive Attack. If Nara is flying and dives at least 30 feet straight toward a target and then hits it with a melee weapon attack, the attack deals an extra 9 (2d8) damage to the target.

Magic Resistance. Nara has advantage on saving throws against spells and other magical effects.

Mute. Nara’s oracle curse renders her mute—she can’t speak, use verbal spell components, or use her captivating song as a result. This same curse, though, grants her the ability to cast all spells as if using the Silent Spell metamagic trait without modifying that spell’s actual level. In addition, Nara can communicate telepathically with any creature she is in physical contact with. She can also maintain a telepathic bond with one specific creature at a time by taking a full-round action to link her mind to that creature during telepathic communication. Currently, she shares this link with Kikonu, even though, ironically, the two are not speaking. Nara can change the target of her telepathic link once per day.

Wind Mystery (2/Day). The first time Nara hits with a melee attack on her turn, she can deal an extra 16 (3d10) cold damage to the target.

Spellcasting. Nara is a 6th-level spellcaster. Her spellcasting ability is Charisma (spell save DC 13, +5 to hit with spell attacks). She regains its expended spell slots when she finishes a short or long rest. She knows the following warlock spells:

Multiattack. Nara makes two attacks with her flaming arrows.

Flaming Arrows. Range Weapon Attack: +4 to hit, range 300/600 ft., one target.
Hit: 6 (1d8 + 2) piercing damage plus 7 (2d6) fire damage.

Poisoned Talons. Melee Weapon Attack: +5 to hit, reach 5 ft., one target.
Hit: 6 (2d4 + 3) slashing damage plus 7 (2d6) poison damage.

+1 Spirit Emblem.