Lansweeper pulls antivirus information from assets in two distinct ways, as documented here: https://www.lansweeper.com/kb/123/managing-anti-virus-software-reports.html
Firstly, Lansweeper can retrieve antivirus information and status from the WMI (Windows Management Instrumentation) protocol on your Windows computers. Keep in mind that the WMI class that stores the antivirus information and status simply
does not exist on Windows servers, which makes it impossible to detect the status (enabled/disabled and up to date or not) of anti-virus packages on Windows servers. You can identify anti-virus records pulled from WMI based on the little "bug" icon.
Alternatively, when your anti-virus software can't be found in WMI, Lansweeper also looks at the software list in the Software tab of a computer's web page (which mimics Add/Remove Programs) and verifies whether an installed software package is part of the list of known anti-virus software found in the web console under Software\Anti-Virus Settings (see screenshot). Keep in mind that you will not be able to get a status (enabled/disabled and up to date or not) via this method.
You can add Sophos anti-virus software under Software\Anti-Virus Settings, but keep in mind that you need to use the exact same spelling as seen under your Windows assets' Software tab or use a wildcard(%) as seen in the screenshot below.