So, if you have the agreement of the other parent, then yes, you can include an order for first right of refusal in consent orders. They usually read something like this: That when the parent with whom the child is spending time is unavailable to care for the child, that parent shall offer first opportunity to care for the child to the other parent. You can also seek this as part of your interim and final orders.
However, you really need to consider if this is a good idea when you and your ex are obviously high conflict. It's just another thing that you and your ex would need to communicate about, which creates more opportunities to fight.
We had this order entered into consent orders, and it resulted in a domestic violence order application not 12 months after the consent order was made. On one occasion, when we had organised for my stepdaughter to spend time with her grandparents by way of a sleepover, her mother called her solicitor, the grandparents, three different police stations and the federal police, then requested a welfare check, all because she felt it contravened the order around first right of refusal. Not exactly an order that reflects the child's best interests when it results in police intervention any time she goes to see her grandparents, is it?