The below worked for me.
npm install sharp
copy the sharp folder from node_modules and paste in the node_modules of framework7-cli
from
C:\Users<your username>\node_modules\sharp
to
C:\Users<your username>\AppData\Roaming\npm\node_modules\framework7-cli\node_modules\sharp
or
Remove the "sharp" directory in "node_modules" then run "npm install --ignore-scripts=false --verbose sharp" and that should work perfectly
npm rebuild --verbose sharp