I would go with a sub-folder if passing DA is your goal. As far as I understand it, DA is not considered by Moz for sub-domains. Here is a similar post on the same topic. I hope it helps.
https://mza.bundledseo.com/community/q/is-moz-da-inherited-from-tld-for-all-subdomains-on-the-tld https://mza.bundledseo.com/community/q/is-there-a-way-to-get-the-domain-authority-of-a-subdomain
