Use robocopy to exclude directories containing a file
I tested this and it worked for me:
@echo off
echo.
set /p "Source=Please specify the source folder: "
echo.
set /p "Destination=Please specify the destination folder: "
echo.
set "Source=%Source:"=%"
set "Destination=%Destination:"=%"
pushd "%Source%"
for /f "delims=" %%a in ('dir /b /s /a ^|find /i ".nosync"') do echo %%~dpa>>"%~dp0nocopy.txt"
popd
xcopy "%Source%" "%Destination%" /e /h /r /exclude:nocopy.txt
del /q nocopy.txt