Similar to this question for Apple, is there anything that my stepdaughter can look up or turn on that shows her I am currently checking her location using Find My Device such as notifications, a log, etc?
Yes, there is a notification that will appear when you locate the device.
WARNING: This could prevent other notifications from appearing.
To disable the notification, navigate to (Version 8.1.0, may be different on older versions)
Settings -> Apps & notifications -> See all X apps -> Google Play services
You should also be aware that there are applications that can fake the location of the phone, and that will effect Find My Device.