I'm planning to develop both a paid and a free version of my plugin for LF marketplace. Does Liferay supports this scenario with something? Or does someone already faced this situation?

Thanks in advance,
-MR

Link https://www.liferay.com/web/developer/marketplace/app-pricing can be helpful to you.

Thanks but I did not find anything regarding my scenario. What I am looking for is something (framework, apis, hints, etc.) to best handle two version of the same plugin (say one free and one paid)

I do not think there is any such framework, api etc.

Ideally, it should go same as other software/application, like provide some basic features as free and crucial/important features as paid.

Ultimately, I think that is going to depend on how you build your own app. You might have a property that enables or disables functionality based on its "type". Or you could use scripts to include or exclude certain functionality at build time.

When it comes to submitting it to the Marketplace, however, you will need to create two different versions (i.e. a "Lite" version and a paid version).