in suitescript, are you able to create a record via xml?

I dont think so since how will you save the XML to the DB. To do that you will have to use record.save or nlapiSubmitRecord which do not support XML.

You could take the node values stored in the xml, parse/format/covert them if needed, perform a record.create and map the fields. Importing, saving and creating an xml file to the NS file cabinet is very possible. And using JSON to get key value pairs and apply them to a new record type is pretty doable