In Shield all of the Pokemon are exactly where they are normally. Download for Windows (EXE version) Download for all other platforms (executable JAR) Since there's no longer a download page with a changelog for each version, you can see the list of changes per version by clicking here. The current release of the Randomizer is 1.7.2, released. Locate the executable file in your local folder and begin the launcher to install your desired game. Click the 'Install Game' button to initiate the file download and get compact download launcher. Then, install the Universal Randomizer application and follow the instructions for downloading.
If you don't, you can download them from the LoveROMS website. To randomize generations 1-5 of your Pokemon game, start by making sure that you have a Pokemon ROM and emulator installed.