Hi!
Well, the licenses stand for one end product, usually that means one domain as well, but there can be exception. Basically, if the domains are of different topic, and not only used as to organize the contents on the same topic, then separate licenses are needed legally.
This topic reply from an official Envato employee should explain it in details: https://forums.envato.com/t/theme-subdomain-license-in-blogger/120362/10?u=wpdreams