There is a problem with using ZFS from the jonathonf ppa - at some point the shipped and hopelessly outdated zfs module is loaded, preventing the newly installed/built module from loading, later on breaking ZFS support. The error looks like this:
failed: [ansible-debootstrap] (item={'poolname': 'rpool', 'devices': ['/dev/sdb3'], 'options': ['ashift=12'], 'fs_options': ['canmount=off', 'mountpoint=/', 'compression=lz4', 'atime=off', 'normalization=formD']}) => {"ansible_loop_var": "item", "changed": true, "cmd": ["zpool", "create", "-o", "ashift=12", "-O", "canmount=off", "-O", "mountpoint=/", "-O", "compression=lz4", "-O", "atime=off", "-O", "normalization=formD", "-R", "/mnt/bootstrap", "rpool", "/dev/sdb3"], "delta": "0:00:00.011030", "end": "2019-06-25 23:19:50.791048", "item": {"devices": ["/dev/sdb3"], "fs_options": ["canmount=off", "mountpoint=/", "compression=lz4", "atime=off", "normalization=formD"], "options": ["ashift=12"], "poolname": "rpool"}, "msg": "non-zero return code", "rc": 1, "start": "2019-06-25 23:19:50.780018", "stderr": "cannot create 'rpool': invalid argument for this pool operation", "stderr_lines": ["cannot create 'rpool': invalid argument for this pool operation"], "stdout": "", "stdout_lines": []}
The problem is a version mismatch between the module and the installed zfs utils. Using the old ZFS version works.