The 4 year / 2 co-op plan requires no overloading and would use Summer 1 freshman and sophomore year for classes. This is true for all majors at Northeastern. It’s also worth noting that AP/IB courses can cut down the needed classes by a semester or summer. Given Northeastern’s 4 credit x 4 course schedule, overloading is nearly impossible to do and highly discouraged, especially given the flexibility of summers.
Here’s a full list of patterns of attendance: https://registrar.northeastern.edu/wp-content/uploads/sites/9/ref-udc-poa-ugd.pdf
Major plan examples show one to be illustrative but they are not major specific unless specified.