Hi @Reedsy 

Couple of things to note here:

1) What you have stated is correct, there is no OOB functionality or script functionality available through which you can do a pagination or filter records and send everything in a single export set.

Solution:

What you need to do here is create multiple export set and then in Export set definition please make sure to apply a filter based on Created or Updated so that only for a certain period of time the records are sent.

Hope this helps. Please mark the answer as correct/helpful based on impact.

Regards,
Shloke