how to create in the hierarchy new stage ?

[Noa Tsruya]

I want to add one more stage between Epic to user story that called Feature.

the hierarchy need to be :

Epic

Feature

User story / task / bug

sub task

Is this possible without special plugin?

[John Funk]

Hi Noa - Welcome to the Atlassian Community!

No, you can't create another stage or layer between Epic and Story as the new Feature would be at the same level as Story. 

You can go above Epic with Theme or Initiative, but you would need to have a Jira Premium Subscription to do that.