DarkUI is updated so ask there if the author is able to help you.
Edit:
Just saw you already did it, so please do not add multiple threads in the forum and ask for help if you have not gotten any response at the addons "directly".
Did you press ESC->settings-> add on settings->Dark Ui and configured it to use the PS4 icons (if it is possible then there somewhere!)?
You could try to just logout, find the file "ShaderCache.cooked" which is normally located at c:\users\your windows username\documents\elder scrolls online\live and delete it.
This will rebuild the texture files and fix missing/wrong ones.
First login after deleting the file will take a bit longer then normal. This is no reason to worry, just wait.
Also did you try what is written at the DarkUI addon description? Though it might be the same like only deleting the ShaderCache.cooked file...
Code:
Troubleshooting
Restarting the game is the best way to be sure that all textures reload. I find there are a number of textures that are cached and will not reload with any number of /reloadui's.
Here are some steps that will often correct problems:
Uninstall DarkUI.
Reload the game completely without DarkUI.
Reinstall DarkUI.
Reload the game completely with DarkUI.