DarkMatter
DarkMatter is a resource pack which gives priority making mods UI's dark.
This project started as a fun and just modifying the UI's with darker ones. I started with few mods that I use in my modpacks, but I can get requests and work on getting more mods into dark UI.
You can requests mods compatibility using Discussions on GitHub Repository.
I never had in mind to stole the original mods UI's. I just changed the colors of the original ones.
The resource pack could have some issues/UI not well made, you can simply open an Issue on Github Repository or commenting down below here. (Priority to Github)
Mods Compatibility