IIUIC, there is the following configuration in EAP 7.3

<subsystem xmlns="urn:wildfly:microprofile-metrics-smallrye:2.0" security-enabled="false" exposed-subsystems="*" prefix="${wildfly.metrics.prefix:jboss}"/>

that should be migrated as

<subsystem xmlns="urn:wildfly:metrics:1.0" security-enabled="false" exposed-subsystems="*" prefix="${wildfly.metrics.prefix:jboss}"/>

However, after the migration, the default prefix is wildfly instead of jboss.