One of the Problems in using the Avast One product range is the Settings are different as are the components included. Generally more components and less configuration more for users that don’t dig into programs to change default setting, for most users this is fine. This is why I have stuck with Avast Free.
I have it in Avast Free, see attached screenshot, click to expand.
This shows where it is in Avast Free if you can try and find the equivalent location in Avast One.
The feature was renamed last year, and you should be able to disable it in the File Shield → Advanced Settings → Analyze unrecognized files. Please let me know if this works.