Cannot complete the install because one or more required items could not be found.
Software being installed: Agree 2.3.3.201809041210 (com.rockwellcollins.atc.agree.feature.feature.group 2.3.3.201809041210)
Missing requirement: Agree 2.3.3.201809041210 (com.rockwellcollins.atc.agree.feature.feature.group 2.3.3.201809041210) requires 'org.eclipse.equinox.p2.iu; org.osate.core.feature.feature.group [2.3.3.vfinal,2.3.3.vfinal]' but it could not be found
I have OSATE 2.4, I tried to install AGREE from
https://raw.githubusercontent.com/smaccm/update-site/master/site.xml
and got: