Notice: There is no legacy documentation available for this item, so you are seeing the current documentation.
You can if you are using a WordPress multisite installation. For more details see this article: Will AffiliateWP work on a multisite installation?
Otherwise, know that AffiliateWP will only track referrals and visits on the site that it is installed on. This will be the same WordPress site where you have your e-commerce, membership or other supported integration. You can also have multiple integrations on the same site. See the full list of supported integrations.
If you would like to promote sales or landing pages on additional websites, this is possible using the External Referral Links add-on. This will require the additional sites to also be WordPress-based.