linux56 doesn’t have the zfs module, obviously. Architect would need another rebuild with a newer kernel, then the zfs module would be available during install.
The team is working on something else right now. Once that is done, probably @Chrysostomus will have another look at Architect.
With ZFS for the root partition always make a backup of the system, because you won’t be able to chroot into it from a live USB to repair it in case of a breakage. The only repair possible is to restore a backup. But making backups is easy which makes it less of a problem. That’s what I understand about ZFS for root on Linux.
Edit: I was a bit wrong, see below, you need an ISO with kernel headers and/or zfs extra module to be able to chroot. I case Manjaro doesn’t support it, create your own iso.
You can. You just need an ISO with the either the zfs modules or the kernel headers on it. As long as you ensure you have an ISO with zfs modules on it, you should be fine.