You can try Eclipse Director and put com.beck.ep.feature.group as an argument for -uninstallIU
The complete command for this:
eclipse -application org.eclipse.equinox.p2.director -uninstallIU com.beck.ep.feature.group
(Use eclipsec.exe on Windows.)
You can specify the installed functions to find the correct identifier with:
eclipse -application org.eclipse.equinox.p2.director -listInstalledRoots
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