Those are my favorite ones, some of then have a skill system, all of them are visual novels with romance, some of them are finished and some are a WIP:
Ebon Light (has a skill system)
When The Night Comes
The Neptune Diaries
Aloners
One Thousand And One Days
As We Know It (I think it has a skill system if I remember correctly)
Dark Nights
Cinderella Phenomenon ( I think it has a system as well)
The Lady's Choice
This, My Soul
Monstrata Fracture
Mystic Destinies: Serendipity of Aeons
The Blind Griffin
Halloween Otome (skill system, mini games, point system)
Andromeda Six
The Spanish Privateer
Zodiac Axis
Aurore: Five Princes (day planning & skill systems)
Mnemonic Devices
Anoldor (a demo is out- a bit similar to Queen's Crown)
Silent Voices
Royal Alchemist (day planning & skill systems)
Gilded Shadows (a demo is out, I think it has a skill system)
I know it's a lot, sorry! I hope you find something you like~ <3