I got good and bad news: my own WM did it Xmonad style, but I have not updated it in years. If there is enough request I might revive it (also X11 though, so not fitting the bill).

See https://github.com/Kintaro/wtftw It handles screens the exact same way Xmonad does, because it was modeled after Xmonad. The config is entirely done in Rust, so it allows for a lot of hackability. On reload, the config gets compiled to a dynamic library and the WM restarts itself, passing the current window IDs to itself to "reload".

But I was meaning to pick up a new project in 2026 for myself. So maybe a CL based Wayland WM with an Xmonad style?