Here is the dreaded command:

sudo mmdebstrap -v --debug --architectures=riscv64 --include="debian-ports-archive-keyring" sid /tmp/riscv64-chroot "deb [trusted=yes] http://deb.debian.org/debian-ports/ sid main" "deb [trusted=yes] http://deb.debian.org/debian-ports/ unreleased main" --aptopt="DPkg::Pre-Invoke {\"sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 84C573CD4E1AFD6C\";};" --aptopt="Debug::RunScripts 'true';"

I've tried all combinations and the latest prefix of [trusted=yes] brings me a bit further in the progress bu it still fails with:

W: GPG error: http://deb.debian.org/debian-ports sid InRelease: The following signatures were invalid: EXPKEYSIG 84C573CD4E1AFD6C Debian Ports Archive Automatic Signing Key (2020) [email protected]

My question is how to pre-import the gpg keys so it won't fail.