All this stuff is subjective to each source but PFF has a metric that is very similar for QBs. It's TWP or Turnover Worthy Play. They say that Stafford had 14 of those in 2020 or 2.2% of his dropbacks. That percentage was good for the 4th lowest BTW.

Goff had 18 TWPs or 2.9% of his dropbacks. He was tied for 12th lowest.