HELP! Computer keeps restarting even after full reset....

I'll let Old Toad comment on your etrecheck report. The advice I'll give you is to stop letting or putting your Mac to sleep. Sleep the display only. The last two versions of Mac OS have had so many sleep/wake issues that it doesn't make any sense to allow sleep. See if that helps.

I don't see any of the usual suspects in the report.

One of the diagnostic entires mentioned power state. Try the following;

How to reset the SMC of your Mac - Apple Support

Reset NVRAM or PRAM on your Mac - Apple Support

Also disconnect your Seagate EHD and run without it for a while. If all is good then plug it back in and test. If the problem begins when the Seagate is plugged back in change ports and test and, if necessary, change cables and test.

Be aware that you have the slowest iMac offered by Apple at the time of purchase: 8 GB RAM and a 5400 rpm hard drive. But that's not the reason for the Kernel panics.

Since in your previous post we did an entire erase and you still have issues, locate an Apple Store for service: Apple Store - Find a Store - Apple.

Cheers,

Jack

Download and run Etrecheck. Etrecheck is a diagnostic tool that was developed by one of the most respected users here in the ASC and recommended by Apple Support  to provide a snapshot of the system and help identify the more obvious culprits that can adversely affect a Mac's performance.

IMPORTANT:

Before running Etrecheck assign Full Disk Access to Etrecheck in the Etrecheck's Privacy preference pane so that it can get additional information from the Console and log files for the report:

Also click and read the About info to further permit full disk access.

Copy the report

and use the Additional Text button to include the report in your reply.

Then we can examine the report and see if we can determine what might be causing the problem.

You’re very welcome! Frustrating that we have to do things like that with macOS but maybe someday they’ll get it worked out.