I've tried different apps like foxfi but it doesn't hide tether usage. I haven't tested USB tethering yet because battery drains faster than it charges and seems to randomly disconnect even with installed drivers. I don't mind using USB tethering if it hides usage but it's pretty faulty in my experience.
PdaNet isn't the only app that promises to hide tethering activity from your carrier, but it's definitely one of the best and most well-known. Most carriers are worried enough about PdaNet and Personal Hotspot Hide & Unhide for Apple iPhone - YouTube Nov 02, 2018 'PdaNet' Updated to Hide Tethering from Carriers | Cult of Mac May 05, 2011
3 Best Tethering Apps for iPhone - iPhone Topics
(2019) How to Hide Text Messages on iPhone by Hiding Feb 12, 2019 Can a VPN hide tether usage? - HowardForums
How to Hide Apps on iPhone And iPad 2019 without Jailbreaking
Nov 11, 2019 The Best iPhone VPNs for 2020 | PCMag Jul 13, 2020 How do I turn off Internet Tethering? - Apple Community