How do I prioritize time in queue (customer to agent) over agent to agent calls(internal)

By definition what you are asking is not configurable for agent queues: https://docs.aws.amazon.com/connect/latest/adminguide/concepts-queues-standard-and-agent.html

Workaround is to create a queue for each agent for this purpose so you can control the PRI and Delay, the only downside is hitting the number of queues limit if you have a lot of agents and regular queues.