@ahmadka,
Do you mean a keylogger, or some "parental control" or "policy" or similar type of tools?
The thing is that no AV should give that type of "approval" for such tools. As with many other things in life, they can be used for different purposes, and avast (or any other security tool for that matter) shouldn't be responsible for taking such decision; only you can.
Essentially, that's the concept of "PUP": Potentially Unwanted Program. Such a software could be potentially useful and wanted, or could be a risk and unwanted, depending on the user/target and the use/goal.
You could add temporary exceptions / exclusions to avast shields so to be able to download and install such a tool, but you should really know what you are doing. To be clear, I am just answering to your question, but I am not actually recommending any particular action. It's up to you and it is your own responsibility.