Most likely the laptop has a hardware issue with the Logic Board which is unfortunately common with the MBPro 16" (2019) model. I hope you have a good backup. In the past year or so, there have been a number of posts on this forum where people who had this specific model laptop repaired discovered the replacement Logic Boards also suffered issues (some users have reported they had the Logic Board replaced two times....some within days of the repair). I personally do not recommend spending any money on repairs as the money is better put towards a replacement laptop.
You can run the third party app EtreCheck and post the complete report here so we can examine it for clues. If you are running any anti-virus apps, cleaning/optimizer apps, or third party security software, then perhaps that is the problem, but I doubt that would be the whole problem with this specific model laptop. Those types of apps just make troubleshooting even more complicated since they have been known to cause Kernel Panics. My guess is you will likely see a large number of "ProxiedDevice-Bridge" panics listed.....this would be related to the T2 security chip & usually indicates a hardware failure. You may even see some other Kernel Panics as well.
You may want to choose "Shutdown" from the Apple menu instead of just sleeping the laptop to see if that helps, but it will only mask the underlying issue (or it may still occur depending on hardware failure since an SSD failure is most likely to occur when waking or powering on the system).
