Generally speaking, the quality gate for a project isn’t something we expect to change from one scan to another. A team would generally benefit from the standard of what passes/fails being consistent across time. Can you share why you’re interested in such an approach?
If you truly need to set the quality gate for a project prior to a scan, you could do so via our web API, the documentation for which is included in your SonarQube instance in the footer of most pages.