Can I use assets of Adobe stock for more than one client with extended licence, enhanced license?
No. One license per client. Clause 6B of the Stock T&C's (bolding added by me)
(B) Client Use. You may license and use a Stock Asset in combination with other content or materials as part of a
project for the benefit of a client (“Client Project”), provided that you purchase new licenses for any additional use
of that Stock Asset by you on your own behalf or for the benefit of any other client. In connection with a Client
Project, you may permit your client to use the Stock Asset under enforceable written terms no less restrictive than
this Agreement. Notwithstanding the foregoing, you must not (A) resell licenses to Stock Assets or (B) use a Pro
Image in a Client Project.
Ok thanks. What do you mean (B) use a Pro image in a Client Project?
What is pro image?
No. You need to licence for each client separately.
A Pro image is a special subscription for high-demand customers.
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).
can I give the client XD file for project or I need purchase new licenses for any additional use?
For the same client, you do not purchase a separate licence if the licence is not yet exhausted. For a different client, you need to buy a new licence. That is also true for our own use.
If you transfer the original file, you will need to transfer the licence to the client. The client has to adhere to the licensing conditions. Transfer license to a client - Adobe Support Community - 11990240