International site: .es or .com/es

[paula]

Hi, our Spanish site is currently living on our [website].com domain (as .com/es) but our application form has been recently set on a separate domain application.[website].es. As a result, we can't track where applications came from cause once a user hits the form, GA is treating it as a new session. We are now trying to decide if it's better to move our application form to our .com/es domain or maybe move the entire Spanish site to .es (rather than .com). What are the benefits of doing one over the other?