Hi Neethu,
according to the b2b help the module is used to convert EDIFACT message standards into XML. I your case you have flat file comming from AS2. you can use message transform bean to convert flat file to XML in sender as2 adapter. Or you need to define ED XML converter. Please refer the below link
SAP PI: Using the B2BADDON EDI<>XML Convertor Modules - Basics
You configure the communication channels of any Process Integration adapter with the PLAIN-XML converter module to convert business documents encoded in EDIFACT message standards into XML and the other way round. It must be configured in the sender and receiver channels based on the business scenario. The PLAIN-XML converter module runs on the SAP NetWeaver Process Integration Adapter framework.
You use this procedure to configure the parameters of the PLAIN-XML converter module.
regards,
Harish