recipe calls for 4 large apples. what is the weight equivalent

In addition to advice so far (go by coverage, volume, cooking off water), here are some descriptive weights of large, medium, small apples, amount needed for a pie, amount in a bushel, etc.
https://whatthingsweigh.com/how-much-does-an-apple-weigh/

This one by Dr. Babs? Hopefully she’ll check in but since the apples are a layer in the batter I would say exact weight isn’t important, but be sure to follow the instructions in regards to letting all of the liquid evaporate

https://food52.com/recipes/7569-ginger-apple-torte

Ginger apple torte

Which recipe are you looking at? If for instance it’s a deep dish pie you’ll actually want to go by volume, probably ~6 cups, and actually for a cake too, because different types of apples will weigh differently depending on water content. If we know what you’re baking maybe we can help figure it out!