Syncing of order and shipping states

In Drupal 9, I have defined the following order workflow for Drupal Commerce:

miss_pomela_fulfillment_processing:
  id: miss_pomela_fulfillment_processing
  group: commerce_order
  label: 'Miss Pomela Fulfillment, with processing'
  states:
    draft:
      label: Draft
    pending:
      label: Pending
    processing:
      label: En preparación
    packed:
      label: Ready to ship
    fulfillment:
      label: Shipped
    completed:
      label: Completed
    canceled:
      label: Canceled
  transitions:
    place:
      label: 'Create order'
      from: [draft]
      to: pending
    process:
      label: 'Process order'
      from: [pending]
      to: processing
    fulfill:
      label: 'Mark as ready to ship'
      from: [processing]
      to: packed
    ship:
      label: 'Ship'
      from: [packed]
      to: fulfillment
    complete:
      label: 'Mark as completed'
      from: [processing, pending, packed, fulfillment]
      to: completed
    cancel:
      label: 'Cancel order'
      from: [draft, processing, fulfillment, pending, completed]
      to:   canceled

I'm trying to understand how to sync the order state with the shipping state the way I need.

Right now, with this workflow, the shipping state changes automatically to Shipped when the packed state order is set, so when the fulfill transition is occurs. But what I want to have is the shipping state as Ready when the state order is packed, and shipped when the state order is fulfillment.

I have tried to find out how to tell the shipping module how to set how to synchronize both states but I'm a bit lost.

Any ideas?

There is no configuration solution for syncing states between these items. It's ordinarily managed via custom event subscribers. Your code reacts to a given order transition and then loads a shipment and applies whatever transition you think is appropriate. There are examples of event subscribers in core if you need a reference, e.g. the OrderAssignSubscriber in the payment module that assigns payment methods related to an order to the same user account as the order is being assigned to.