All PayPal module settings have website or store view configuration scopes.
Try this way:
Please go to admin panel -> system menu -> configuration -> payment method.
after that you can select which store to config in the dropdown (Current Configuration Scope)
Now, you can select to enable the payment method for each store.
Also, to allow yourself to enter per store configuration options for paypal, open up the following file:
This file contains all of the configuration options for paypal. You’ll notice that most items have the following xml in them:
Some also have:
For those options that you want to configure on a per store basis, simply paste:
underneath the :
After doing this you’ll need to clear your configuration cache.