I don't think it's possible automatically.
Unfortunately, There is no event receiver triggered when creating/ created a site collection to handle this using event receiver.
However, you can adjust this manually by locking down the content database as the following:
Steps
Before creating a new site collection, you should plan to do the following:
Check also Lockdown the web application content databases
Another workaround
Using PowerShell to Create a SharePoint Site Collection in an Independent Content Database
Download the full script at PowerShell: Create a SharePoint Site Collection in a Separate Content Database