Open the "Import" menu in Eclipse, either by right-clicking on the Packing Explorer or using File -> Import -> ...
Import 1/2: Click "Browse" and search for your checked-out local copy of the Tweety repository
Import 2/2: Configure options Don't forget to add the name template '[groupId].[artifactId]' under the "Advanced" tab.
Overview of all TweetyProject libraries
Optional step if you want to use TweetyProject libraries in another project you created: Add the TweetyProject libraries to the Java build path of the other project. If the other project
is not in the same working set, add the libraries to the "Classpath", not the "Modulepath".