According to the docs it looks like it should be possible to configure server-ssl-context without client-ssl-context. There are server-requires-ssl and client-requires-ssl attibutes which seems to support this. 

However, due to the server-ssl-context attribute dependency on the client-ssl-context attibute it is not possible to configure this via CLI as it always fails with

Failure: WFLYCTL0380: Attribute 'client-ssl-context' needs to be set or passed before attribute 'server-ssl-context' can be correctly set

Here is the code declaring the dependency on client-ssl-context:
https://github.com/wildfly/wildfly/blob/main/iiop-openjdk/src/main/java/org/wildfly/iiop/openjdk/IIOPRootDefinition.java#L179