Hello again,
If you already checked the provided information and ruled out hardware issues, I would recommend to run the Mac diagnostic. Later, if you don't find any issue with the diagnostic result, I would recommend to reinstall macOS as you told us.
Apart from that, I understand your are thinking on installing a macOS beta on your Mac. I would not recommend that, the beta software from Apple it's only recommended for not primary devices, as it may contain bugs or other problems that can make your computer to loss data and other issues.
“Install beta software only on non-production devices that are not business critical. We strongly recommend doing so on a secondary system or device, or on a secondary partition on your Mac.” - Apple Beta Program
I send you some documents that you can follow easily to run diagnostics on your Mac: Use Apple Diagnostics to test your Mac - Apple Support
And also, this other document for reinstalling macOS: How to reinstall macOS - Apple Support
🙂 I hope I have helped you and I remain at your disposal for further questions