In the 2018 July Hotfix, Microsoft added support for Azure AD accounts in Workflow. There’s a lot more information in Lucas Miller’s post: Dynamics GP 2018: Organizational Accounts and Workflow
Dynamics GP 2018: Organizational Accounts and Workflow
Install, Upgrade & AdminGP 2018
Archived post from 2018. Dynamics GP and the links it points to have changed since; check current documentation before relying on version-specific steps.