Columns, statuses and the workflow go hand-in-hand. How you add a status is via the workflow, so you won't be able to add a status without changing the workflow.
I'm not sure why you don't want to change the workflow, but you are able to make a copy of it so that this change wouldn't affect other projects if they use the same workflow.
Introducing Jira Cloud for Excel Here at the product integrations team at Atlassian, we are thrilled to announce the new Jira Cloud for Excel add-in! This add-in lets you export Jira data directly ...
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