https://bonsai.sensu.io/ to get the new plugins for CentOS 8, some of them don’t have a version for CentOS 8.
here the list :
sensu-plugins-http
http-checks
sensu-plugins-cpu-checks
sensu-plugins-memory-checks
sensu-plugins-chrony
Example : Sensu assets | Bonsai asset index - sensu-plugins-cpu-checks Asset