You can restore the missing power plan settings simply by running several commands in Command Prompt.

Search for “Command Prompt” either right in the Start menu or by tapping the search button right next to it. Right-click on the first result which will appear at the top and select the “Run as administrator” option.
Type in the following set of commands one after another and make sure you click Enter after typing each one and wait for the process to finish and display a “process successful” message:
Note: The last command can only work on Windows 10 versions after the 17101 build as it’s related to restoring the Ultimate Performance Power Plan available for the newest Windows 10 builds for workstations.

powercfg -duplicatescheme a1841308-3541-4fab-bc81-f71556f20b4a

powercfg -duplicatescheme 381b4222-f694-41f0-9685-ff5bb260df2e

powercfg -duplicatescheme 8c5e7fda-e8bf-4a96-9a85-a6e23a8c635c

powercfg -duplicatescheme e9a42b02-d5df-448d-aa00-03f14749eb61

Restart your computer and check to see if the power plans are back where they belong.