Which Android AV products are the least chatty, requiring minimal user input/interaction? I'm not familiar with any on the market as, for my sins, I'm an iphone user, but would like one for an elderly relatives device.
In my opinion check out BitDefender or Zemana. But to be honest, if they do not install a lot of apps and only install from the Play Store they will likely be fine.
If you opt for one that is solely an antivirus and doesn't include extras like cache and RAM cleaning then user interaction will be kept to a minimum.
Any to those above should be fine. Just test them all and see how you feel about them yourself. Hands on viewing in person usually narrows the field.
Add Sophos to the list. Scans as things are installed. Does daily scans. warns of low reputation apps = unknown to them = not frequently used. Does a wonderful blocking of phone calls where the calling number is not in your list of contacts. Has privacy advisor, lists insecure settings. Incudes loss and theft configuration. No bloatware. Quiet.
In my opinion, an AV for Android is useful only if it comes with a browser protection. Sophos is a great choice, but it's not very battery friendly. Other good options are AVG and Avast (they both have a FREE and PRO version)