Confirm there are not already settings or features that do what the shop is asking for.

The "UU" tracking numbers attached on orders are redirecting customers to USPS website, Shop wants the "UU" Tracking numbers attached on orders to redirect to UNIUNI Website to track the orders

Link : https://www.uniuni.com/

What does the shop want the product to do?

Shop want this feature to redirect customers to UNIUNI Website to track the orders.

Link : https://www.uniuni.com/

Why/how would it improve sales or efficiency?

Customers are facing issues while tracking the orders in this way which redirects them to USPS website the orders cannot be tracked, This feature will help customer's and shop for smooth tracking and delivery experience.