I have recently changed my name. How does this affect my EUSS documents?
You should use your names as shown on your identity document when applying for pre-settled status. The application will ask if you have ever been known by any other names. If your details change after having applied for pre-settled or settled status, you can update your details online following the steps here: https://www.gov.uk/update-uk-visas-immigration-account-details. Your details should still match the details on your identity document as your (pre-)settled status is linked to this.
The update system changed recently and you can now change names on the online system. The system will show the following steps you need to take. You will need to fill in a form, provide your ID and send the ID to the Home Office for verification.