First, I should figure out what a license key does. Generally, a license key is a code that activates software, verifies the software is genuine, and allows access to all its features. For Kutools Plus, it would be similar. But I need specifics on how it works here.

Another angle: The license key's role in activating cloud-based features or online services associated with Kutools Plus. Maybe data synchronization across devices or collaborative features.

Wait, the user wants a "detailed feature," so maybe include sections on purchasing, activation steps, supported versions (like Excel 2010 to 2021? 365?), features unlocked by the license key, and maybe something about renewal or upgrades. I should also check if there are any limitations or what happens if you don't have the license key.

I think that covers a lot. Now, organize this into a coherent feature article, making sure each section is detailed but not too technical. Use clear headings, bullet points where necessary, and ensure that the information is structured logically from introduction to conclusion.