I don't know the particular products you mention, but in general it is possible.
The easiest way would be if the other products offer update sites, you could then simply set these up and install into your main Eclipse (Help > Install New Software...).
If they don't provide an update site, they might provide a download of their features and plugins. You could install these into your eclipse by copying them to eclipse/dropins/features
and eclipse/dropins/plugins
.
If there is no separate download, you could try to find the specific features and plugins from the other Eclipse installation's features
and plugins
folders and copy them to your main Eclipse dropins
folder.