Is drush.wrapper used anymore for Drush 8? How to use for Windows?
No, don't use drush.wrapper. There is a new tool in town - Drush Launcher. It works on Windows too since it's PHP based - just follow step 4 in the installation instructions. (Step 2 and 3 aren't relevant on Windows, and step 1 is just a normal file download on Windows.)

Added: You should remove/rename the global Drush if you have any. If you need it, check out the fallback option for Drush Launcher.

PS! Also the Linux/Mac people should use Drush Launcher.