You do not need to stay on-site in order to use the Sorcerer pass. The Sorcerer pass is also a hopper (same 2pm rule). You just need to be a
DVC member eligible for membership benefits to purchase it (or FL resident).
The only way staying onsite will benefit you while using a Sorcerer pass is park reservations and generic Disney resort benefits (early entry, deluxe extended evening hours, $LL at 7am, etc). For park reservations you will pull from separate resort guest AP availability AND be able to book for length of stay rather than just hold five park reservations at one time.