As part of the April 2020 wave 1 release for Dynamics 365 Field Service you can now have dependent requirements and these can be scheduled in sequence using RSO (Yes this feature is not available for manual or any bookings done using schedule assistant).
You can define relationship between requirements using the successor relationship of a resource requirement

Once you define the the relationship between the requirements and run RSO, RSO is going to schedule the requirements in sequence and the same would reflect on the schedule board too. This is how it’s going to look like on the schedule board:
