It seems you want your KDE Desktop looks like this?
https://www.reddit.com/r/unixporn/comments/1fknhp2/hyprland_first_time_using_actual_arch_instead_of/
You only need 2 extensions
- Panel-Colorizer as @perletero mentioned
- Kronkite as @perletero mentioned.
I have posted a few settings for Plasma Colorizer here 
Take your time. Read the manuals. Ask questions if you have any.