https://wccftech.com/16-inch-macbook-pro-has-minor-cpu-performance-improvements-but-gpu-upgrades-are-fast/

Apple recently launched the 16-inch MacBook Pro with a new scissor-mechanism based keyboard, larger display, slightly thinner bezels, improved thermals, faster graphics and better speakers. While the new features have received a lot of appreciation, not many have noticed that Apple has re-used the same old 9th generation Intel processors that were also available in the 15-inch MacBook Pro. This means that you should not expect considerable CPU performance upgrades when upgrading from a 2019 15-inch MacBook Pro to a 2019 16-inch MacBook Pro.

The 15-inch MacBook Pro was updated in May 2019, with Intel's 8-core Core i7 and Core i9 processors, running at 45W. These were Intel's 9th generation processors and were no slouches in the performance department. A fully specced 15-inch MacBook Pro would be equipped with a processor that could Turbo Boost up to 5.0 GHz. The only other change in these laptops was an improvement to the butterfly keyboard so they don't break as often.