Thanks for posting in the Community. I'd be glad to assist you with printing W-2's.
@Anonymous is correct in that QuickBooks Online does support printing on plain paper. Additionally, there is the option to print on 4-part perforated paper and coming later this week the option to print on 3-part perforated paper should be available. For more insight into this, I recommend this article, which goes over the steps for printing a W-2: View And Print W-2 Forms.
I'm confident this will help you get back to business.
Let me know if you have any questions. Wishing you well.