Thank you for post!
I understand that you would like to know is it possible to test the Entra ID connect seamless SSO in one Windows machine without GPO policy.
You can use the Staged Rollout feature which is allows you to selectively test groups of users. for more readings Migrate to cloud authentication using Staged Rollout
Also, you can test the feature for a specific user with the Group Policy. for more readings Test Seamless SSO
Hope this helps. Do let us know if you any further queries. Thanks,
Akhilesh.
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