As others already said.

From a process standpoint, you can so long as those are Standalone or State Only returns.  You can check this article for each state's e-file method:

https://proconnect.intuit.com/support/en-us/help-article/electronic-filing/state-e-file-methods-stan...

From a professional practice standpoint, I would hesitate doing that unless I'm 100% certain that the federal return is complete as accurate because state returns would, inevitably, start with numbers from and positions taken on a self-prepared federal return.