The items from the following plugins were removed from the workflow:

Transition: Reopen

System post functions removed from this transition:

• Update Issue Field

Transition: Reopen

System post functions removed from this transition:

• Update Issue Field

Workaround

Use the Cloud-to-cloud migration (beta) tool

• Create a new company-managed project
• Associate any existing workflow you wish to export with this new project
• Go to <your site name>.atlassian.net/jira/settings/system/migration/dashboard and migrate the single project

See the article What migrates in a cloud-to-cloud migration for Jira for more information