The Deploy a Sharded Cluster page is missing one crucial information regarding deploying a CSRS sharded cluster: the replica set names for the config replica set and each of the shard replica set should be different. Otherwise, adding shards would fail at the later steps with:

{
  "code": 20,
  "ok": 0,
  "errmsg": "A shard already exists containing the replica set 'replicaset'"
}

Suggestion: Add the naming restriction wordings (possibly inside a green "Note" box) under:

• Create the Config Server Replica Set
• Create the Shard Replica Sets