You missed one - Capital M have an excellent fish and chips as part of their weekend brunch menu.
Thanks for the update! Adding it below:
Capital M: Fish and Chips fillets of fish fried in a light beer batter with fat chips tartare sauce & a tart parsley salad (RMB 268+10% as part of their 2 course brunch, which includes a cocktail and limitless tea or coffee, or three courses for RMB 298+10%)
Also another I forgot:
Lily's American Diner also serves Fish and Chips -- lightly battered cod with french fries and coleslaw -- for RMB 69