You asked your question in the wrong animated section. To answer the question, normally when you link in any object from another file, you can’t alter it without creating a proxy (Local Copy) of the item that you imported from that blender file. The only way linked data can be updated is by going back to the source file and make the changes there.
But a quick answer to your question is … Yes… It is most certainly possible to “Link” items into your file from other files (Libarary Files) instead of just “Appending” them…