You will be able to apply for naturalisation directly, however, as part of your application, you will need to show how you have met the requirements. This would mean that you would have to prove that you have been living in the UK for at least the last 5 years and exercising treaty rights. Therefore, the documents you would normally submit for the PR application, should be submitted as part of the naturalisation application.
I hope this answers your question. If so, kindly rate the answer and provide feedback.
If you have any questions, please do not hesitate to ask.