Okay, it isn’t so easy, but the following help you to the right track.
If you don’t have a separate service-account for Local AD connection, then you can use this:
dsquery user -name MSOL_AD_sync
If you have a service-account, replace MSOL_AD_sync with that one.
Next type: DC repadmin /showobjmeta <DCNAME> <DN of MSOL_AD_sync or the service-account>
See for LastLogon or UserAccountControl attributes, they will lead you the way.