About us — CachyOS → an archbased OS optimized for x86-64-v3/v4 CPUs.
You would be able to add the Arch KDE-unstable - I would not say witout issues - as Plasma 6 is as 
edge as it can be.
Don’t use it on a production system - you will be displeased - even grumpy or having a 
attack.
Another great test flyer is KaOS_Test - Browse /iso at SourceForge.net derived from Arch Linux using pacman as package manager.
Perhaps a FrankenJaro can be created injecting Arch Linux KDE-unstable in between [core] and [extra] - now that would be a monster 
Switch to Plasma 6
The following is ONLY if you are well versed in solving issues.