Quick an easy way to cross build Kicksecure Xfce on amd64 (Intel / AMD) for arm64.
With git tag 15.0.1.7.4-developers-only
sudo -E ./whonix_build --build --flavor kicksecure-xfce --target raw --remote-derivative-packages true --repo true --arch arm64
(--remote-derivative-packages true: Whonix build script now optionally supports installing packages from Whonix remote repository rather than building packages locally - Optional. Not yet tested without. Will post an update once that is done.)
Build complete but did not test boot.