You can activate & deactivate a plugin via a custom URL.
For example, consider that you are using the WooCommerce Plugin. You likely don't need to load the WooCommerce CSS/JS files on contact pages then. To do this:
Step 1 : Enable status -> on
Step 2 : Rule Type -> URL
Step 3 : Select Plugins -> WooCommerce
Step 4 : Plugin Status -> Deactivate
Step 5 : save changes.