Not sure if this matches exactly what you're looking for but here's Hoenn:

• Religions surrounding mythological pokemon (e.g. arceus, tapu lele, etc.) and related rituals do exist in this setting
• There's some members that have fleshed out religions for certain Pokemon
• Avatars exist in this setting.  They're someone who is chosen by a legendary and can summon them / embody their traits.
• Set in modern Hoenn region.
• Legendary pokemon are a frequent occurrence on the site.  The last event featured four legendaries making their entrance at the end to choose avatars.
• Signups for an event based around Darkrai are currently open
• Coordinator contest system,  more site-wide events and plot developments are just over the horizon

Intriguing. I didn't look much into Hoenn before since I'm not sure how I feel about the whole faction thing, but maybe I'd take a closer look this time. Thanks!

Perhaps not immediately what you had in mind, but SHINE BRIGHT! seems to fit your general search:

• anime/manga fcs.
• medieval-esque setting, give or take some technological advancements!
• powers. all the constellations inhabit some type of pre-determined powerset -- like the people of the constellation of aries is known to inhabit fire manipulation/generation, divinity, and war; aquairius is known for their aquatic abilities and their sound manipulation, etc. -- but you are free to work that into your character's powers/abilities how you see fit, and we allow creative freedom as long as characters are reasonable and they fit with/derive powers from a particular kingdom. advisors, especially, have a lot of lee-way, seeing as they are able to change into one particular small animal, and in/out of human form, and can manifest items for the senshi and help the royals when need be, but any other ability they have is up to you and their birth does not have to necessarily stem from their alleged constellation like other characters.
• we also encourage different character types, like princes, princesses, queens, kings, knights, and senshi of each constellation. we also offer people the chance to play "corrupted" characters, or a chance for their characters to "turn to the dark side" by becoming chaotic and following the wicked evil main antagonist on site who wants to take over the galaxy and overthrow all the royalty.
• although the backstory and occupation may have to be altered to fit the site, Rhyme seems like he fit right in with the royals of Sagittarius -- who have storm-like powers and have a strong intuition. Or, perhaps, he could also be applied as a Capricorn -- who are known for their wisdom, precognition, and plasmakinetic abilities(which could be more "magic"-like, given their energy-based powers).
• It is recommended that you are familiar with Sailor Moon, but not entirely required! If you're interested, and would like to know more or have any questions about the site, please feel free to contact me at eclipsedreams#5600.

I hope to see you around! And, if not, I hope you can find a place to call home. Good luck on your endeavors!~

hrmmm... the character roles might be too defined for me, but I'll think about it. Thanks for the ad!

Might not be 100% what you're looking for, but I figured I'd offer City of Outcasts. We are a site with no face-claims, but we allow people to use animanga images as they see fit. We are set in one location, but our lore is quite loose. Though our main setting is modern, there is a medievalesque outer world that I'd liken to Azeroth in terms of modernity, and we allow players to make up locations both within the city-state and the outer world. We allow any power so long as it isn't used to the detriment of other RPers and storylines, and just about any race that you can think of.

If this isn't what you're looking for, we understand. Finding the perfect site can feel so difficult. Good luck in your site search!

Mrm... I'm not too sure what I think of a modern D&D setting with Bahamut being basically evil, but I'll consider it, I guess. Thanks for the ad!