In our app we have 2 datetime pickers that we're using as a date range filter.
For dateFrom control we have [max]="dateTo.value" and for dateTo control [min]="dateFrom.value".
For example we can set both controls to the same day but dateFrom time to 02:00AM and dateTo control to 01:00AM.
In this case dateFrom > dateTo but validators is not applied at all and control marked as valid with no errors.