The fieldChange smart value currently only provides the Team name, not the Team ID.

{{fieldChange}}

ChangeItemBean{fieldId='com.atlassian.jira.plugin.system.customfieldtypes:atlassian-team', field='Team', fieldType='null', from='null', fromString='engineering', to='null', toString='dev'}

Consequently, to retrieve the previous team ID, we are required to employ a workaround. This involves leveraging the GraphQL API (/gateway/api/graphql?q=teamSearchV2) to search for all teams corresponding to the 'fromString' value. Subsequently, we need to employ complex branching logic to differentiate between teams, based on their name. This approach is not entirely reliable due to the possibility of different teams having identical names.