KDE developers are working hard on Plasma 6 Wayland. See also KDE Plasma 6 Development Progressing Well, Plasma 6 Beta Possible In A Few Months and KDE Plasma 6 Wayland Session: “It’s Been Working Great!”.
For example, you can install Neon Developer Edition via KDE neon: Live Images. After installation, you can upgrade it to KDE/Plasma 6,
sudo apt update
sudo apt install neon-settings-2
sudo apt full-upgrade