Free trial licensing question

Are you talking about the 30-days free trial (which is a subscription for a year, but it can be cancelled anytime during the first 30 days without being charged)? The licence you can acquire with that subscription are coming with a standard licence, which cannot be used for merchandising (i.e. printing on T-shirts and selling). But yes, you can use them on your website.

What is important is the licence type you acquire. Standard licences have more restrictions than extended licences. An extended licence can be used for merchandising.

Look here for more information on licensing: https://community.adobe.com/t5/stock/links-for-licensing-terms/td-p/11366788
(Disclaimer: As always with licensing, this is my interpretation of the rules. I think they are correct and advice is based on reading and interpreting the licence terms and on fair use for both the buyer and the artist/stock company, but I cannot rule out that my interpretation is wrong. I'm not an Adobe employee).