Hi,
I'm Rodrigo and I'll help you.
Press Windows + R, type shell:AppFolder and press enter. On the folder, locate the Minecraft Launcher, right click it an select "Create shortcut". It will create a Desktop shortcut.
On the batch file, point it to run the UWP app shortcut from the Desktop.
Example: start %userprofile%\Desktop\Xbox.lnk
(.lnk is the shortcut extension)