There is the possibility to change family icons; details about how Visualizer manages the family icons and the procedure to change them can be found in:
“Managing CI Family Icons” at:
https://docops.ca.com/ca-service-management/14-1/en/using/configuration-management/cmdb-management/cmdb-visualizer-overview/managing-ci-family-icons
and:
“How to Change the Icon of CI on the Visualizer” at:
https://docops.ca.com/ca-service-management/14-1/en/using/configuration-management/cmdb-management/cmdb-visualizer-overview/how-to-change-the-icon-of-ci-on-the-visualizer
No possibility, in the tool out of the box, to modify the mouse-over feature.