I called my pool 'dinosaur' and three datasets, you guessed it, triassic, jurassic, cretaceous
Steps:
sudo zpool create -R /backup -o ashift=12 dinosaur /dev/sdb2
sudo zfs set dedup=on dinosaur
sudo zfs create -o encryption=on -o keyformat=passphrase dinosaur/triassic
sudo zfs allow nikolay create,destroy,mount,snapshot dinosaur/triassic
sudo zpool import dinosaur
sudo zfs set mountpoint=/backup dinosaur
sudo zfs load-key dinosaur/triassic
sudo zfs mount dinosaur/triassic
sudo rsync -a /run/media/nikolay/nick-home/ /backup/triassic/
sudo wipefs -a --backup /dev/sdb1
sudo zpool add dinosaur /dev/sdb1