HI,
Thanks for purchasing our plugins.
The plugins do not reply on the license key to work so you can download and setup on any install you would like for testing.
The license gives you access to automated updates so typically you only need to enter that on the site you want to have that.
If you have more questions I encourage you to check out our license articles:
https://theeventscalendar.com/knowledgebase-category/purchase-install/
And if something is still not clear then create another support question and we can help out.
Cheers