Convert IWA to PDF

It doesn't look like that any direct way how iWork files (.iwa) can be converted to any other format exists. These .iwa files are found inside compressed documents from iWorks (.pages, numbers etc.) and replaced the previously used XMLs that were utilized for the document structure.

All this means that iwa to pdf conversion is extremely unlikely.  If you want to convert your document, you will need to convert it as whole, not just a part from inside. Some sources claim that it might be actually possible to somehow decode IWA files (they feature Snappy compression) and rebuild some kind of "old" version of iWorks documents, but that seems like highly unreliably and complicated way.

Simply put, it is impossible to convert IWA to PDF directly.
Thus, there is no so-called iwa to pdf converter or a free online .iwa to .pdf converter to be found.