Can I use it in terminal?

[cyw3]

No description provided.

[suhininalex]

You can try to run inspection from the command line: https://www.jetbrains.com/help/idea/running-inspections-offline.html. Also there is a new version of this plugin as a part of Ultimate IDEA with better results and kotlin/groovy support (try EAP/nightly version).

[cyw3]

Do you have a plan that this plugin become a tool independent on IDEA?
So that I can use it and no need to install IDEA.

[suhininalex]

The main idea is to use duplicate detection on-the-fly in the IDE. So one can use advanced features to remove duplicates interactively (like navigation, comparison, refactoring, etc.).
Thus there is no plan to create stand-alone tool.