So I was wondering, if one uses a scanner what does that information end up doing? Is it able to be accessed somewhere?

Yes, when you use a scanner it allows you to see a pets genes/mutations (both carried and vis), all of their colors and stats before you catch them. It is also useful against bosses, as it allows you to see their stats, to determine what they are strong/weak against.

Additionally, I think if you scan a pet in battle and then catch it, you don't have to use a genetic testing kit on it. Fairly sure on that, but I may be wrong.

It's true, a scanned pet will be tested when captured. I scanned an Uncommon pet before capturing it and it's marked at having been tested.

In battle whe you use a scanner a screen will pop up and show you all the information on the pet. Once you close out of the screen you can access it at any time during that battle by clicking on the scanner icon next to the pets name.

So what's the difference between each scanner?

The standard scanner is a one-time use scanner while the exceptional scanner has an infinite amount of uses.

Thanks