Features are just text files, so you can import them into any other software just like you would any other text file. This is probably not a good idea though.
You can also store the text that makes up a feature in other pieces of software. However something very important happens once you start implementing a feature which is that the feature itself becomes code. Once the feature is code it has to live with the rest of the code in the codebase, and more importantly it has to be able to be changed/refactored as the codebase develops.
So if you are wanted to facilitate the creation of new functionality by passing around features in software like Excel or Word than thats fine, if a little bit clunky - you might be better of using your ticketing system, or some other collaborative tool. However if you are trying to use feature files to monitor what functionality exists in the system and to show what work has been done, then that won't work at all well. You'll end up making your development very much harder and much more expensive. These things are best done by ticketing systems and reviewing the actual application.