those API endpoints all accept a
id parameter which you can use to read 25 transactions before this id. Some NEM nodes also allow you querying by hash, but not all, so using the ID might be a better choice because all nodes allow that.
Basically the /account/transfers/incoming will return 25 transactions or less every time you query it. The first time, you would get the last 25 transactions with the last created (also highest ID) being the first transaction in the result set.
Next time when you query the endpoint again, you would specify the oldest ID that you got from the result set, as the
id parameter to the API. Then you will get the 25 transactions or less that happened before the given transaction id.
Hope that helps!