4 aircraft and 7 cabin layouts, from the 737-700 to the 787-9. Pick one for its seat map, the best seats and the seats to avoid.
There are seat maps for 4 Shanghai Airlines aircraft here: the Boeing 737 MAX 8, the Boeing 737-700, the Boeing 737-800 and the Boeing 787-9.
The Boeing 787-9, with 285 seats: 30 Business, 28 Premium Economy and 227 Economy in its main layout.
The Boeing 787-9 has Premium Economy in at least one layout.
The Boeing 737-700, with 31" of seat pitch in Economy and seats 17" wide.