I appreciate hearing that you tried the reinstall. I think it was worth a try.
So, now you have hardware issues to think about.
Have you looked at your battery yet? Swelling, if that is present, is often easy to see (and can be more obvious, even without opening the bottom cover on your MacBook. Don't misunderstand, battery swelling is not a cause, it's a known result of use, and aging of the battery, so a quick inspection of your battery would be a good next step, and can tell you what happens next, and - even without any evidence of anything physical, the fact that your diagnostics indicates that your battery is heading toward failure (all batteries fail eventually, or at a minimum, make your laptop a less portable computer.)