The Borla S-Type axle back system will make the exhaust louder with a different tone. I had a 2017 2SS Fifty edition myself with the Borla S-Type on it. It sounded great and the Fifty edition has factory burbles tuned in, which was not really a thing back when the Camaro's first came out.
The Mishimoto intake isn't doing anything but making a little extra noise. The GM tune was not made for that intake so having it installed by GM may or may not have helped anything. Knowing GM, the changes were probably nothing fuel related anyway. GM can't just change fueling without going through all of the government steps to maintain emissions and fuel economy. The factory fuel trims can handle the fuel changes for that intake.
For a short time, GM sold this intake, rebranded as a GM part for the Camaro along with the GM tune. However, it was not carbon fiber, but Cold Air Inductions was the manufacturer behind the scenes. This is the intake the GM tune was made for.
https://www.coldairinductions.com/sh...0aAkVkEALw_wcB