How can I change the feed format in Effortless Feed?
This article will explain to you how to change the feed format on the Effortless Feed app
To export the feed using Effortless Feed, select a feed format that is compatible with the platform you want to export the feed to

Another option is changing the format manually: copy the URL and change the ending from csv to tsv or xml.
Example:
https://apps.adcore.com<key>&format=csv
to
https://apps.adcore.com<key>&format=xml