If your state requires that you amend your return in order to get the refund from unemployment income exclusion, you will choose to amend your federal return, which will also amend the state return. When you get to the checkout process, you will choose to mail (not e-file) the federal return, because as you state you do not have to amend the federal return. Then you will choose to e-file the state amended return. That being said, not all states all amended returns to be e-filed so you may need to mail in your amended state return.