[mothered]

unless best buy/walmart/amazon/microcenter have some sort of central database?

Collectively, they don't.

I've been racking my head thinking and can only think of a few other than the four I listed. IEMs, lighter gopro models, watches, sunglasses, and jewelry all work?

Can't generalize, It depends on the Item weight.

For Instance, define "lighter GoPro models". The term "lighter" could be anything.

And do you have any other favorite items to EB?

There are many tech-based Items and apparel that capture my Interest, but the first port of call when EBing, Is to Identify the precise weight.