Atlassian has released the patch activeobjects-plugin-5.0.2-d60f2531d.jar, and applying this patch makes the Reports and Timesheets for Jira app support Jira version 9.2 and above, which uses MySQL 8.0 as the backend.
We recommend manually applying the patch until Atlassian bundles the patch activeobjects-plugin-5.0.2-d60f2531d.jar as part of the atlassian-bundled-plugins. For more information, refer to How to manually apply the Atlassian Active Objects plugin patch.