I have a recipe for sweet corn bread and it calls for fresh corn and it is very hard to find fresh corn in winter; can it be replaced with frozen corn?
Personally I find frozen or canned is usually much better quality taste and texture wise to the fresh cobs. Good quality canned/frozen sweet corn is picked and frozen/canned within hours of picking whereas cobs in the market could easily be over a week old by the time you get it home.
So yes, you can easily substitute canned/frozen for fresh.
Same goes for peas.