As such there’s no out-of-the box activity which can do image redaction.
We do have the capability to do text redaction where you can specific blacklisted and whitelisted characters in Text Extractor Activity which needs to be considered while extracting the text. Refer this link for more info.
In case if you have the code base in Python / C# / PowerShell which can redact image then you can definitely integrate that in the Automation Studio using the Python Script Activity / MicroBot / PowerShell Script Activity.
You can refer the below Knowledge Base links for more information.