In most cases a cluster will act as one. But if you need to make adjustments to a single or multiple node(s) you can do that by changing the cluster configuration under Hosts -> Cluster -> Config overrides. This page will show the whole configuration as plain-text. When adding overrides there is a pattern that you need to follow, each override is done by copying the name and value for a key parameter then adding the serial number in parentheses.
config_key name value name (serial) value2
For example if we want to use different certificates for our inbound listener. We start by copying the name (tls) and value (pki:<id>) that we want to override. Then we add the serial number in parentheses after the name (tls) for each node that should have a different certificate. The last thing that we need to do is to change the value so it matches the certificate we want to use.