This has been planned for quite some time (actually about a year now)......
Dracut is a much more generic Intiramfs tool then Mkinitcpio (pretty much Arch only) and way better maintained.
A first version of Dracut is up in the [build] repo. It does not include any KaOS specific config files. So to test, you will have to run dracut command manually.
Testing locally right now with an image created with:
sudo dracut --hostonly --no-hostonly-cmdline --kernel-image --zstd --kver 5.11.11-1-next /boot/initramfs-linux-dra.img --no-early-microcode --force
Boots without issue, just some mismatches with local udev rules, not matched by that image (yet).
ISO testing (internal) with Dracut will start shortly too, if all goes well, expect Dracut to be on the next stable release.