No, because issues live in projects, and one of the most important things a project does is provide consistent configuration of the behaviour of the contents.
I know what you are looking at when you say "bucket" and the simple answer is that you should consider a JIRA project to be the same thing as a bucket in the legacy systems you've got the idea from. That will mean you don't need to worry about issue security schemes, and just get the permissions right.
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