wlrobs has issues for me with 2 screens of different densities. With xdg-desktop-portal-wlr the Pipewire route will work as well.

My favorite way to record on wlroots compositors is wf-recorder, which seems to be lighter on resources than the others.

There's also a fork of SimpleScreenRecorder (with similar issues, unfortunately).

Here's an overview of screencasting tools for wlroots based compositors like Sway and Wayfire: https://github.com/solarkraft/awesome-wlroots#screencasting