Hello,
1 project means 1 End Product, you can have 2 sites with different names, for example, “my-project.com” and “my-test-site.com” (live one and staging), if they are 1 end product, XStore can be activated there using the same purchise code.
You cannot buy a WordPress theme once and use it for more than one client/end project.
If you will face an activation limit error, contact us, and we will check activations and help you.
Regards