You will need to as lenovo this question. You cannot simply add/replace a card.
And, you may have problems if you do:
yes you can just replace the card.. I just need a new one.. I just dont want the 8260 again as they are known to have many issues.
its the size etc that is the concern. I know the 8265 will just mount exactly in its place as they are identical, sockets etc and antenna hook up.
the 9260 I am not sure.
I have replaced the card already, as this is my second 8260. its simply an upgrade question
I replaced the 8265 with the 9260ac for the HT160 support, in my Dell Inspiron 7577 never had issues with Intel cards TBH other than the 7260ac which was fixed driver side. The 8265 is a m.2 card and practically any m.2 wireless card of the same size including the 9260ac should work. The 9560ac however is the same as the 9260 in functionality but it is a two part solution with part of the wireless chipset function being in the 8th gen Intel CPUs and the wireless adapter part being the other half.
Also ensure that Lenovo has no whitelist preventing upgrades as HP & Lenovo were notorious for that though now I hear they no longer do that. Additionally as Hill said go over regulations.