Can Gmail be configured automatically to print all received email attachments?

I use Automatic email manager. You can set different email account to download new emails from 1 minute to hours later. It will also sent the atached file to a folder on you computer

You could give File Processor a try. But make sure the interval to check gmail is > 10 minutes as google adds limitations to protect its services.

It's the client that prints email, not Gmail itself. Though your browser, used to view email on the Gmail site, may not offer this feature, another client can do this. For example, if Gmail were to be read using the Mozilla Thunderbird email client, then that client can be configured to print any queue, including the Inbox. For Thunderbird, you'd need the free FiltaQuilla add-on. If you want to automatically print attachments, as well, you might need another add-on, e.g., Printing Tools.

There are numerous alternatives to Thunderbird, as well.

Having said all that, I would not want to print every email attachment. Some might be hundreds of pages, or contain malware. It's safer, if longer, to download, let the AV scan the attachment, and then print it.