Sophos AV always runs double instances of it's app. How do I just have 1 running? I run Sophos Anti-Virus on macOS Mojave and it always runs two instances of the app. It has 2 menu bar icons and it runs as 2 separate processes. When I attempt to quit or force quit either of the apps in Activity Monitor, it automatically just runs them again (I assume as a security measure). 

Is there a way to just have 1 running?
Simple ... Uninstall Sophos.   Check with Sophos on how to uninstall. 

Simple put,  Apple attempts to provide all the malware detection and removal you need in Mac OS X.

"Effective defenses against malware and other threats" by John Galt
https://discussions.apple.com/docs/DOC-8841

"Avoid phishing emails, fake 'virus' alerts, phony support calls, and other scams"
https://support.apple.com/en-ca/HT204759

"MalwareBytes Anti-Malware for Mac Removes adware and malware Revives your Mac."  MalwareBytes has a more restrictive filter for adware than Apple. MalwareBytes has come to be accepted as the only malware detector you should consider.  For those pestered by browser attacks consider MalwareBytes.

https://www.malwarebytes.org/antimalware/mac/