Adita tells me that Plasma Bigscreen is ready Qt 6 and KF6 happiness. I've not tried it yet and and he's still working on the apps. It was released as part of Plasma for the later 5 releases, but it's too late to add it into the Plasma 6 release so I'll get it working in neon unstable and if all is well then I'll make a standalone release alongside Plasm 6.0.
Jonathan