FileMaker exports found sets so once you pull up the records you want in a found set, you are good to go for the export.
To get a found set from a list of ID's can be done in one of two ways:
a) Put such a list of ID's into a single field with returns separating each ID. Use a relationship that matches this field against your data table's ID field. Then the Go To Related Records script step can pull up your found set.
b) A looping script can either generate a series of find request with one ID specified in each request or the looping script can use extend found set to find one record at a time and add it to the current found set. For examples of such scripted finds, see: Scripted Find Examples