storagenode info --config-dir <insert your storage node config dir here>
But redirect to the file:
storagenode info --config-dir <insert your storage node config dir here> --json > node1.json
Then add them all to the array:
jq '.' -s node1.json node2.json node3.json > nodes.json
now you should be able to import them:
multinode add nodes.json
Or using some bash:
for n in node{1..10}.json; do
multinode add $n
done