There are several suggestions for installing psycog2 to Windows on StackOverflow:
Since the Gramps 5.2 AIO installs pip (package installer for Python to help the Addon Manager with prerequisites installation), the process for installing probably going to differ between the Gramps 5.1.x (or earlier) and Gramps 5.2.x versions.
So which of those StackOverflow suggestions (if any) looks appropriate for the different Gramps versions?
Note that there is some chatter about whether adding pip has been a successful experiment. It isn’t part of the macOS installs. So pip might disappear from the 5.3 AIO package.