Hi Benjamin,
Thanks for reaching out to our Stock team. Regarding the query above, the digital media agency that manages the SEO and social media of your organization should follow all the licensing terms and restrictions of Adobe Stock mentioned in Stock Licensing & terms FAQ: Where can I find the terms and licensing information for Adobe Stock?
Additionally, for all the unmodified images that are being used on your blogs, an image credit has to be given to the photographer, however, if the images are modified the credit line is optional.
Please note: It entirely depends on what type of modifications are being made, for example, if it's just the colour change then the credit line must be included. However, if the changes are on a wider level, the credit to the photographer becomes optional.
Lastly, the licensing rights purchased by Digital media agency of the organization cannot be transferred to you, they can definitely license an asset on behalf of a client. However, please note that if they want to use the same asset for different clients, the asset must be licensed separately for each client. Kindly refer to Common Questions, Adobe Stock for more information.
You may also reach out to our support team Support FAQ: How can I contact Adobe for support? for further clarification.
Let us know if this answer your question, please feel free to update this thread in case I have missed something.
Regards
Twarita